I agree. The earlier in your journey you are, the more you’ll benefit from focused effort. You’ll just get to 10k followers etc. faster if you put all your time into one platform. If I was just starting out, I’d stay focused on one place until it can pay the (basic) bills or adds up to a meaningful amount, then diversify into another. Diversifying too early is also a problem — then you won’t make meaningful progress anywhere. Always a tradeoff.
I shared some more thoughts on the issue in general here: https://entrepreneurshandbook.co/diversification-vs-focus-the-hardest-tradeoff-for-entrepreneurs-5a55e896256a