idk. it's more like having 6 magazines about hyundai cars, i never know which of the ones to buy because they all look the same, and if i just buy half of them, the article i'm interested in is guaranteed to be in the one i didn't buy.

and one day they all vanish after neither one sold enough copies to make profit.

it splits the community, what is a bad thing if the community isn't super big to begin with. and it adds extra confusion to new users. and extra effort for people who want to stay up to date. and if i have a niche question i can't just ask many people at once. i first have to look up in which community i need to ask. or i just ask in every community and annoy the people who subscribed to multiple ones.... it's just not a good solution to anything...

the one thing where this would be a good thing is if the communities were reasonably different. different in topic, focus, a noticable different culture of discussion or moderation, something drastic enough to warrant people splitting up ... like your analogy with the nyt or bbc. but it's simply not the case for these communities.