Having said that, if your goal was to contribute to projects in C/C++, why wouldn't you start with those languages and their ecosystems? I'm saying this as someone who started programming in 2001-2002 whose first languages were C++ and Java. Of course, back in those days, we didn't have all the resources available to new programmers today, so I was learning from books!
In any case, perhaps it is worth reassessing your goals. I do think part of the problem you're having is likely to be down to not working on Python particularly often, so if that is a thing you really want to do, then I suppose you'll have to make some time for it. As with most things, I think little and often is better than a lot every once in a while.
On another note, I think I started with Linux around 2002 and was a Slackware user for a long time though I've recently switched to openSUSE.
In any case, perhaps it is worth reassessing your goals. I do think part of the problem you're having is likely to be down to not working on Python particularly often, so if that is a thing you really want to do, then I suppose you'll have to make some time for it. As with most things, I think little and often is better than a lot every once in a while.
On another note, I think I started with Linux around 2002 and was a Slackware user for a long time though I've recently switched to openSUSE.