Along these lines (and based on opinions heard from different rabbanim on previous misfortunes in Jewish history), this post expands on possible connections. Again, these follow the mussar I've learned, plus Jewish perspectives of similar events, however, they're still just my own ideas and not more than that.
Withdrawing the Unparalleled Privilege
Our halachic obligations are actually privileges, even if they don't always feel that way.
Serving Hashem b'simcha is one of the most vital aspects of Judaism (and sometimes, one of the hardest).
So Hashem might temporarily withdraw the opportunity to learn Torah in yeshivah, to learn in a frum school, to daven in a minyan, and so on, if we haven't been doing so with enough zest.
Likewise, if we go according to Rav Arush's idea, we see that a quarantine is either a way to separate us from others and/or an effective way to make us spend more time with others (if we have family at home), which can also be both a blessing & a challenge to our middot.
Yearning for these sometimes unappreciated opportunities is a good way to earn them back.
Warm or Cold: Which Way will Things Go?
Imposed quarantines can force us into more face-to-face communication (if we live with others). But for those alone, it forces them into more back-to-back communication (because that's the only way they can communicate in quarantine).
On yet another hand, even people living together can turn toward technological distractions as an escape.
We see this now when a group of people sit in a room together, yet each person is staring into his or her own tablet/laptop/phone.
And on still yet another hand, technology is less available right now (though I don't think we're feeling it so much at this point).
For example, I delayed buying a new printer when my old one crashed. Now the printer best suited for my needs & pocketbook is on-hold in China, even though the store I visited usually carries it. Apple says the quarantines & illnesses are delaying software updates.
The big clincher here is we're all expecting the Internet to remain running.
I don't know how much a working Internet depends on people being out in an office. Other related aspects, like the necessary electricity, does need hands-on people to keep going.
But even with those who escape into their phones or computers at home, we'll still be forced to spend more time with actual people (if we have them around).
Certainly, a downturn in our ability to go out or use other forms of communication opens up more opportunity to spend time in prayer & learning Torah.
Looking into Ourselves for Ideas
Why might Hashem do that?
It's connected to the idea above, that if we don't use a spiritual privilege properly, Hashem might temporarily withdraw it.
So if we invest ego gratification in a mitzvah or perform it with a non-Jewish flavor, then that also cheapens the mitzvah.
In the past few parshas, for example, the Kli Yakar has discussed copiously the intent of wealthy people when they give tzedakah. If there is pride involved, it diminishes the mitzvah quite a lot, even if the actual amount given was quite generous.
Likewise, sometimes people get caught up in a well-intended yet misguided perspective regarding mitzvot.
Sometimes, very precious mitzvot like hachnasat orchim or bikur cholim invite lashon hara or other prohibitions if we're not careful.
Bitul Torah (or just plain bitul) can also be a problem in conversation. Even just taking upon oneself to insert at least one Torah thought into an otherwise tiflus chat can make a huge difference, spiritually speaking.
As much as we can, our get-togethers should consist only of mitzvot & real Jewish simcha.
Some communities love to celebrate mitzvah milestones, like weddings, bar mitzvahs, chalakas, brissim, etc., with a massive investment of money & planning.
The core desire is rooted in the neshamah's awareness of the spiritual beauty of the event.
But the mind & heart can get caught up in the material or competitive or insecure aspects that sometimes end up coming to fore.
Yet even a tiny bit of restraint or looking into one's underlying motivations (even if it doesn't feel like extravagance because so many other people are doing the same) can have a resounding effect in Shamayim.
Another example: In the effort to look nice l'chvod Shabbat or attending shul, some people style themselves in a way to knock people's eyes out.
This too can be remedied by using very small steps.
For example, a little less blush "l'shem Shamayim" or a skirt that's a bit longer or a hair-covering that's a bit more refined or going with regular heels (or even flats) rather than 2-inch spindly heels can have a surprisingly powerful impact in Shamayim.
Also, woman habituated to scarlet-nail manicures can choose a more refined color.
Even though long nails are still a problem within tsniyut, and in some communities nail polish is a big no-no regardless of color, the fact that she's refining herself for Hashem even in a small way is still a VERY BIG DEAL IN SHAMAYIM.
If you're doing it for Hashem, these little refinements can resound far more than imaginable.
Just as one example, Malky Feig’s Mountain Climbers 2 tells of how a young frum woman overcame a bleak diagnosis when she resolved to stop using a soft-bristled hairbrush on Shabbat (because it unintentionally pulls out hairs, which is forbidden on Shabbat, even though she’d bought the soft bristles to avoid such a thing—but it unintentionally pulled out some hair anyway).
Many people will scoff if you focus on such small seemingly insignificant acts, but the proof is in that story and many other stories of this type.
Other people might not notice your efforts, but Hashem sure does.
Small Steps CAN Tilt the Heavenly Scales—YES, THEY CAN!
So yes, seemingly insignificant acts reap huge results...as long as we're doing it for Him and His Torah.
Everyone's on a different level and each person excels at one aspect while struggling with another aspect — and these aspects are different for each person.
Deciding what aspect (no matter how small) to focus on is a very individual decision.
Frankly, I think heeding Rav Avigdor Miller's recommendation not to discuss your process with others is very wise.
(He's repeats this recommendation in several lectures. Here's one example: Rav Avigdor Miller on Friends & Cronies.)
Especially regarding small steps, another person can scoff at your contemplation and ruin everything.
That's not okay.
No matter how small, if you're taking a step in the right direction, then that is GREAT.
It really is.