I've read a similar post from someone else a while back, but can't remember who it was - sorry for that lovely person.
However, I want to bring in a different angle (well, how would you know, anyhow..)
Why does climbing the career ladder happen outside your working hours?
The books that you read, the thoughts you have, the additional tool that you test, the blogs that you read, the people you talk to and tell you something you didn't know which you can use the next day, the mentors that challenge your thinking, ... all that puts you one step further then your colleague.
For context, I am not speaking about that you need to be better than your colleague, it's not the competition, but getting better in what you are already spending a lot of time on.
Now, the whole concepts would mostly only work for you, if your daily work is actually something you like. If you don't like your job and want to switch off afterwards, then no need to do that. If you like your job and limit your "mental focus" to the working hours, might be that others who put in more time will learn more than you.
Might also not be, because you spend time on improv theatre that increases your emotionally empathy which then helps you at work. However, if you only spend time watching TV, playing video games and are not interested at all in something and don't develop any skills, don't complain for not getting further.
Some might rather have the problem, of not being able to switch off or not getting into a different setting, i.e. sports, another project or something which basically still excites them and they learn sth, but they would benefit from the mental switch.