I don’t really think that’s the right framing of the situation. I don’t think that focusing on a particular specialization necessarily means the complete game must be worse, it just means you need to think about the best kind of game that emphasizes the specialty you want to level up. If you want to focus on improving your level design then building a platformer is going to be much more conducive to your goal than building a fighting game. If you want to focus on system design, building an RPG will offer a lot more opportunities to improve than building a visual novel.
Got a burning question you want answered?