If you see something objectionable on Twitter, report it. It will be addressed. The problem that Amazon has with Parler is that they repeatedly informed them about specific posts with violent content and Parler didn't remove them.
And as we all know twitter applies their community guidelines equally on all its users regardless of their political stance.
From all accounts Parler was self-moderated by the community and links such as the following are still present:
https://pbs.twimg.com/media/ErTzgBxXcAAuTkC?format=jpg&name=...