Lately I feel like I'm mentally working at 50% of my capacity. I'm spending the time, but I feel a major loss in focus and motivation.

This is just a rant, but I think some of you might have faced this at some point. Did anything help you lately?

I have been feeling something like that for quite a few years now

Few reasons
1. Ageing. Plays a Primary Role
2. Lack or loss of Enthusiasm. It is hard to be pumped all the time
3. Juniors and the likes taking over gives little reason to feel young and reduces the necessity to prove my Worth (if there is any)

But, I realised it is normal and accepted it. I'm just doing what I could do. Setting up any bar and trying to meet seems futile and against the natural Growth

I know this feeling...
For me it is the first level of "it's time to leave and go on..." somewhere else...

Yesterday was the first time this year I had a solid 60 minutes of uninterrupted code, and it felt rejuvenating, I got in the zone.

Turning off teams + outlook and jumping in is worth it.

I quit drinking caffeine. Sucked at first but after a couple weeks I started to be able to focus longer than before I quit

This happens to me too, but I think it's because I'm bored. A little bit of coffee (1/3 of a mug) usually helps.

Keep following the current trend and you will be a manager rather soon!