If you are getting defederated by 90% of the network, isn't that maybe a strong indication that 90% don't want to hear what you have to say?
Freedom of speech is a protection against the government censoring you. It doesn't mean you get to spread hate and toxicity freely without consequence.
If that is true, it means Mastodon misaligns with probably some 90% of the political spectrum that would absolutely not want to take away her speech, regardless of whether people agree with her.
Which means...Mastodon is a far-left echo chamber. Which doesn't have to be bad, everybody deserves to have their place. I'm just saying it's not suitable for mainstream usage.
I expect clients that combine timelines from alt accounts using different servers to become the norm. Users get all the benefits, with more ability to opt out. If I've got Jim@alt.net on banning-instance, and Mike@tim.com on the banned instance, and their timelines are combined client-side, it's the best of both worlds.