The walled garden social networks have a serious downside compared to fediverse networks and that's the registration wall. If you're primarily publishing press releases and announcements, people will be unable to effectively share through links what you're publishing. Mastodon let's you bypass that while still allowing for the engagement that the other platforms do. And you don't have to play pay to win with the algorithm to get your stuff to actually show up on feeds of the people already fucking following you.