I remember some services send you a message telling you to change your password anytime a new device logs in or even fails to login to your account. That causes most people to pick weaker passwords, since they're not all using manager apps.
Why? Any breach that involves usernames/passwords are account name and password combos that get tried on EVERY POSSIBLE SITE after.
It only takes one pair of username with a reused password for this to work.
Use a password manager, and reset your password if the service has been compromised.
Expecting people to simply memorize a unique, strong password for every single website that they use is unrealistic. Of course, no solution is perfect, but that doesn't mean we shouldn't improve the current situation of people reusing passwords with maybe slight modifications per website.
7BB7DB877943832837046863EF45C252D3A08C92A273F7B665210A6E12701095
Do you have Amouranth's or xQcOW's salted hash from this leak? Might be worth trying to brute force it.
You try on those kinds of accounts because they might have re-used it or the password might be patterned or not completely random, which gives you a chance that the credential might give you access elsewhere.
This is not worth worrying about. If Twitch is making you reset your password, that means you don’t need to hurry because they’ve already locked your account. If your password hash leaked, the important thing isn’t Twitch, it’s every other place you used the same password.