Agreed on what's going to happen to Rivian. Respectfully disagree that Lucid will fail because of the "Tesla cult". Every brand has their crazy fans (AHEM corvette), but that wouldn't kill Lucid. Lucid's going to have a cult of their own. And they're not even trying to compete with Tesla. There's no chance. By the time Lucid reaches the 25k pricing (if they want to) Tesla will be wayyy too far ahead. Additionally, they are very clearly trying to be a luxury brand first. Not transition the world to sustainable energy, but transitioning luxury to sustainable energy. Completely different missions and targets.
Also, I have to disagree with your notion that the Lucid is engineered better. I think there are plusses and minuses to both, and both come out to be even. Yeah the Lucid has more power, but can't use that power as efficiently. 144-146 trap vs. 153 for the Plaid, even with almost 100 more hp. The Plaid is a master at holding power. The Lucid is quite a bit heavier as well. The Plaid is like a scalpel in performance. Additionally, the 924 volt architecture is awesome, but I doubt that they will be able to use the 400 volt Tesla Superchargers, even if they're open to manufacturers, unless there was some type of adapter.
I'll leave off with this: while the Lucid is an awesome car, and as a fan of the brand, I'm excited for them, it's VERY important to remember that things for this small company can go really well, or really bad really fast. Even as a LCID investor, I have to acknowledge that fact. Tesla is an experienced EV manufacturer with the chargers and knowledge to back it up.