That is true of course, although I would think most competent rate limit implementations would set thresholds that deter bots while real users barely notice, unlike what was observed with twitter. Coincidentally, higher rate limits were a paid option. Spam might not have been the primary motivation for rate limits.

Elon Musk said it was due to "data scraping and system manipulation":

https://news.ycombinator.com/item?id=36552324