mstdn.jp has surpassed mastodon.social in number of users! Congrats to @nullkal!
I think timelines were good to find new users before. But now, with large amount of users, the mechanism is not fit to Mastodon. Now we need another mechanism. And Without federated timeline, issues may be solved, I concider.
I hope this text helps you.
Erotic illustrations on federated timeline from pawoo.net arose issues, but to begin with, do we still need federated timeline? Increasing users made federated/local timeline too fast to read in realtime. Now these timelines became almost noises. In the future, they will be completely noises when some kind of PR bots appear.