Besides the fact that Perch's vids are usually "stream of consciousness-type rambling" with hits and misses, the issue is more involved than simply "not doing right by Black characters".
Attempts have been made...some half-heartedly/assedly and some serious, and for any number of reasons (poor creative team choices, uninspired storyline, lack of marketing and promotion, general reader disinterest and/or low expectation) a project will "fail".
In my opinion, we've seen a slight forward push for more diverse characters and PoCs but still...Editorial just don't put as much effort and energy (in whatever capacity) behind unproven IPs and it will take much more than an anthology book once every six to months to gain consistent interest.
And the onus is not just on the Marvel. We the readers decide what wins and what fails...if we don't buy and support the efforts then those Black/PoC books stay off the shelves.