Yes, he was quite popular at one time. It was clearly a well-groomed bit of PR that he was this eccentric billionaire who was using his wealth to forward science and technology for all mankind.

Then it turned out that he's a narcissistic man-child. The mask slipped for me personally when he called that diver rescuing the Thai kids a pedo. His outrageous manipulation of crypto markets came next (exploiting the lack of regulation). Since then, his purchase of Twitter and treatment of Twitter employees has been a staggering shitshow from start to finish. It has absolutely shattered any illusion that he is a good businessman and he's certainly not a good person.

https://www.vanityfair.com/news/2022/04/elon-musk-twitter-terrible-things-hes-said-and-done

I don't know if he's "always" been on the right politically but he's definitely been way more outspoken since he acquired Twitter. And it's not just a matter of "we hate him because he's conservative". No, we hate him because, like any modern conservative, he openly denigrates trans people, blames Fauci for the pandemic, and he continually overlooks or forgives users for racist and hateful remarks.

Before I left Twitter I also saw a few examples of the "fact checking" system calling out tweets from liberals (for very minor distinctions) and not adding disclaimers to easily debunked claims like hiring 87000 IRS agents.