Should I upgrade from Canon EOS rebel T7 to Sony A7iii?

I mainly do portrait shoots only.

I have owned the T7 for 2 and a half years now, and did 6 portrait shoots in 2021 with 50mm lens which I was satisfied with. I just didn’t like the speed of the T7 camera and AF but its not a deal breaker.

I would still consider myself a newbie, and I am wondering if its worth the upgrade especially since A7iii is on sale right now for $1360?

Please explain to me in detail what I am missing out on and how the upgrade would help me with my shoots for next 3 to 5 years.