Unable to detach emotionally from work?

Focus on being "good at your job" not at "making everything better" or whatever you're doing now.

What you think of as doing extra work also ends up causing extra work for other people. You say "Attemtps to communicate with other teams to sync and improve processes were also shutdown... because it's not my responsibility and the team leads felt threatened" - it's almost certainly not that your team lead "felt threatened" (wtf?) but because you caused an extra hassle for them by causing confusion among your coworkers about the processes and practices for communication, documentation or decision-making.

Your time spent "fixing a lot of small things" that nobody cares about means other people have to code review, QA test, merge, deploy etc your work, which as you stated, was not scheduled/prioritized/desired.

An important part of being a team is playing your role, which includes not interfering with other people doing theirs. You see yourself as an unappreciated hero picking up the slack for everyone else, but everyone else sees you as an unpredictable wildcard causing confusion and extra work. Just focus on doing your job well and let the whole team thrive.

Anecdotal(worked for me and a friend):

Find another activity (hobby, sports, taking care of someone, meditation, side-project, anything) and gradually have it replace work in your head.

You won't be able to "detach from work" because the mind (especially in people who like to think) doesn't work this way. You'll have to expel it/push it out.

Any time you catch yourself thinking about work in an emotional way, or outside your office hours, force yourself to shut it down and think about the other activity you chose as replacement.

This process took me years but it's really been worth the effort.

Don't do extra things. Let the sprints guide you. Try to make your code better. The place doesn't want you to do these cleanup tasks without them being approved in a sprint. So next sprint meeting suggest it and only do it if it gets approved.

You need to first understand why you are getting passive-aggressive responses. Just because you think you are doing "other things that no one cares about", it doesn't mean it aligns with what your Manager/Team/Company needs from you to ensure you are effective at the job you were hired for.

Superstars in a team are easy to spot. They not only get their stuff done but do other things that help the bottomline. Problem is that sometimes you may think you are helping the team by doing other things, but you are probably doing it at the cost of your own work.

You are being micro-managed, it's worth comparing your current work environment to what you were told it would be like when you hired on.

If there is a large difference between the position description and reality then you may be able to push back with the hiring manager so that you are given more autonomy to prioritize tasks during sprints.

Ideally your management should be asking you to first do items in set X and then giving you time to work on tasks that you prioritize.

This is why I prefer Kanban over Scrum as Kanban doesn't limit the set of tasks per sprint as Scrum does.

It's in my experience that when one elects to keep themselves busy with A instead of B, it's because they're more adept at A than at B. Doing B requires one to get out of their comfort zone, and doing A let's them believe they're making progress while avoiding having to think about B.

Now that's just me, maybe it's different for you.

If I may ask: how are the sprint tasks different from the other small things you feel compelled to do?