Currently dealing with this in a deep level and it’s absolutely crushing me.

My company used to have teams work on primarily 1 main application with a couple smaller supporting apps, usually in one stack. Members of the team usually had a primary role or area of responsibility. Basically things were more structured and better defined. Even things like requirements were better defined and the integrations points were well documented.

A few years ago they started pushing multiple applications onto teams, including in multiple stacks. Roles are less defined and everyone is just expected to do everything. So you're switching between apps, tiers, and stacks constantly. In some cases they have one code based that includes multiple apps which multiple teams work on. This creates constant changes and small issues in local dev setup. They're really pushing speed and agility, which ends up with poor requirements and designs compared to the past since it's less formal and less thought through.

I went from being a high performer to being a low performer. After years of being lied to, passed over, and screwed over while being a high performer and now being told I do great work in some areas but my day to day work is too slow, I'm completely demotivated and demoralized. I have good credentials and previous coworkers have thought i was already a senior dev, yet I'll never make it to that level. I've been on multiple teams and asked for accommodations such as reduced context switching, but they can't do anything about it because of the way the work is structured. One team even told me they were surprised I stuck around for 2 years because they expected to burn people out in about 1 year. This checks out since they had more than 100% turnover in those 2 years and I was the only one left from the original team. They made a big deal about their contract with Auticon. When asked in an enterprise meeting (by someone else thankfully) what they were doing for employees with similar backgrounds it was crickets - no answer.

I honestly don't know if I can keep this job, even though it's just an early career midlevel position. It sucks to think I no longer have a career with advancement options. If I lose this job I assume I'll end up working at Walmart or something. The stress of an uncertain future and having a family to support is extreme.

I’m in a team. It’s just that what was a team of 4 including our senior tech lead.

Over the past 4 years the other 3 on my team all left.

The only position backfilled was the most junior one, doing 99% html/css/photoshop work.

We have no senior tech lead.

Yes. A stable project, working on the same codebase (updating, refactoring, maintenance) is a great fit.

But the "let's change things for the sake of it", random management decisions based on fads, and so on, are extremely brutal.