I wouldn't say it's overrated. Whether it's the greatest of all time is always gonna be a matter of subjective opinion but it's definitely in the running, there'd have to be many more excellent shows for it to not even be a contender.

I can't think of another show that is as well written whilst also having so many moving parts. It's an incredibly dense show with a vast interconnecting web of characters that touches on a fuck load of relevant societal themes and tells dozens of compelling human stories whilst doing so. That's not the only measure of quality but it's an area where it really does have other shows beat in my opinion.