Isn't it necessary to be on the Twitter platform in order to use Grok? Unlike lots of other people, I still use Twitter, but for those who don't, I would think it is an obstacle to using Grok.

The advantage of using Grok (or any alternative to Google Search!) is that there isn't an entire ecosystem of pervasive prying Alphabet services to go along with it: Gmail, Youtube, Google Play, Google SMS (Verizon terminated its SMS for text and recommended all users use Google instead, in November 2024), Google Meet or whatever they call it, and probably more. It can track you everywhere, and a deliberate effort is required to evade it with alternative providers.