The entire point of Twitter was that there was no such filter, it would just show the tweets of everybody you followed in a chronological order. That's why we are all pissed.
I don't know if that was the "entire point" of Twitter. I am certainly glad that there is a bit of filtering. I recall the old days where most of my feed consisted of noise, today I actually get some value out of it.
Sure. But my Twitter feed is not important enough for me to do something about that. As it is, it's somewhat entertaining (I check it perhaps once a week) whereas if it was unfiltered I never would. So I am at least one person for whom it makes business sense for Twitter to filter in order to keep me engaged.
That changed a long time ago, I'm surprised people are only noticing now. The change was not borne out of malice: like Facebook, they try to filter out accounts with too much noise or which you don't really interact with, to show you only stuff you're really interested in. In the past you'd see all @-replies and a single noisy account could basically flood your timeline, that's hardly the case nowadays.
In the case of Scott Adams mentioned above, it happens to me regularly with tons of people who are absolutely unthreatening. There is certainly real censorship going on inside all these centralized platforms (like deleting content), but Occam suggests this is just Twitter trying too hard.
The shadowbanning and bubbling only started like two years ago. That thing about seeing all replies was changed... I don't know, eight years ago? And that made all the sense in the world and it's in no way censoring or anything... My friends talking to people I don't know is not something I care about. But my friends talking to me and me not seeing it because they are shadowbanned? That's a new low.