Yes, I've had a bit of this effect.
When I was fully in hiding, I found that intense concentration, essentially escaping into a 'flow state' where self-awareness faded in favor of task focus, was a way to escape dysphoria. I was more comfortable in that state of suppressed consciousness. I just couldn't sustain it past several hours due to physical needs of my body disrupting the mental 'flow state'.
Perhaps a year to several months before my 'crash' and coming out last year, though, the anxiety and depression interfered with my ability to enter this state, and I couldn't do that any more. It turns out that the inability to concentrate and focus were symptoms of the depression and anxiety, and were why I lost that knack.
A few months after I started HRT I found that I was able to get back into that 'flow state' and perform well on tasks that required concentration and focus, but at the same time, as I came out to people and eventually started full time life as myself, the dysphoria and the need to escape into myself faded away.
Now, I've lost the knack to entering that 'flow state' due to lack of practice!
I do practice mindful meditation, which involves a 'flow state', but is not particularly good at assisting in focus and concentration on a task. I've been using that to get through things like Electrolysis Mondays, but it doesn't help when I have to do a tax return, a complex financial calculation, or electronics work.
I doubt very much that I lost the concentration and focus due to return of depression and anxiety, as I felt too darn good. I think it is just a lack of practice and a lack of necessity, as it is no longer a survival tool for me.
Just some introspection for you to dig through while you poke around for an answer within yourself...