I also get the downvotes for the GPT thing, and agree with you about 5.5's quality, but TBH I don't think it's Anthropic marketing as just two other things:

1. SamA and his company has a well-deserved bad reputation and Anthropic got some early good PR for basically not being SamA.

2. Claude Code got early head space, Boris and crew basically "invented" this kind of agent, and so has first mover advantage despite its known reliability and cost issues.

3. Most people I talk to haven't even tried Codex for some reason

Also it's uncool to complain about downvotes.