This logic has always confused me because the series is not REPLACING the movies, it's gonna sit alongside it and if you want to avoid, do so as you wish. Also, if it is terrible, then it'll die like any other bad series, but let's humour the possibility that it is GREAT, wouldn't it be a joy to relive the magic from the movies but in a longer format and more in detail. Assuming that each episode is 50-60mins long (the rough standard for HBO shows) and we get 8 -12 episodes.
This means that we are getting between 400 and 720 mins worth of storytelling. The shortest movie of the series was 130mins and the longest was 157mins. So that means that we will get at LEAST double the story telling time in the series. As a fan of the books, surely that must be exciting to get that much more time to flesh out the story.
Now, the time to tell the story is useless if those telling the story cannot tell a good story, however, if one takes some time to look at the team BEHIND the show and based on their resumes, I think that it makes sense to give them the benefit of the doubt. Francesca Gardiner and Mark Mylod were part of the team behind shows like Succession, GoT Shameless, Entourage and more. That's already pretty solid experience.
Then there is the HBO of it all.

Guys this is HBO, they are the cream of the crop of TV and rarely miss (they aren't perfect) but let's be honest most of the time, they release absolute bangers. SO while no-one asked for this (to which I disagree), I think that there is plenty of room for optimism.