I wouldn’t call Scientology a major religion. No credibly survey or source has ever put Scientology membership globally higher than five figures, whereas the LDS says they have 17 million members worldwide. Which may be inflated, but even if they’re padding the numbers a bit that’s still hundreds of times larger than Scientology.

Scientology is good at being noisy and intimidating and having famous members, but it’s never translated into a real mass movement religion.