Does SB want to be on those platforms?
If that's where users you want to reach are, probably so. Social media is a cup half-full, half-empty thing. Yes, we can find fake news, misinformation propagation, people one might question being allowed out in public without adult supervision and so forth on Facebook.
There are also wonderful people of commendable character with wisdom to share.
Much of what's 'wrong' with Facebook is what's wrong with the human race. Facebook essentially gave a public publishing platform to maybe most of the human race? Without much censoring of content or policing who is allowed on the platform. A vast international public experiment in free speech gone wild. Decades ago, you could annoy family, friends and co-workers with your opinions, but that's as far as it went. Now, you can network with like-minded people! Businesses prosper in part by giving the customer what they want. Most people don't want their feed packed with memes and snarky quips from the opposing political party, or a different religion incompatible with their own beliefs. By giving people what they're interested in, of course it creates ideological echo chambers and polarizes people.
Not everybody there stops with that. I'm a conservative; each morning I get the New York Times' free 'Morning' e-mail digest, and via Apple News+ I sometimes read articles from
The Atlantic. I listen to some liberal sources to break out of the ideological echo chamber, and because I know not everybody with brains and something of value to share also shares my religion or politics.
P.S.: I think the purpose of the poll is to get a sense of which social media sites are used
by people who use social media sites. If they add 'none' to the poll, it may be interesting to see the %, but how is that going to help them determine which social media outlets more divers use?