It may not be the only reason, but it's certainly a major one. Also, if safety is a concern, how many dumb ass safety decisions were made by Elmo, so can we lump those in with the 'Elon' bucket?
Because Google has set it up to work. A query parameter is just that it's a parameter for your query. In this case Google has set that parameter to disable AI search results.
I think the only reason they have it and tried this yet is they simply haven't thought about it. I guarantee you if Trump were to read that comment, first of all he wouldn't understand the sarcasm, and would on ironically try and do that.
He does not.