just re-release the original

It wouldn't make money. They screen old classics at my local theaters all the time and the auditorium is never full. I've been to actual screenings of Suspiria and they weren't even sold out, which says something given how rare they are as opposed to being all over the country like a re-release would. Audiences simply aren't that big on paying $10+ to see a movie they've already seen.

It is being remastered (again) in Italy and will have a theatrical screening in Rome. I hope is will be as close to perfect as possible. Can't be buying Suspiria every 18 months for he rest of my life!

That would be very stupid.

The original is a piece of garbage!
It is stupid!
It is boring!
it is not interesting!
it is not scary!
Basically, nothing happens.

I'd pay to see a remastered version of the classic film on the big screen. A remake... no.
https://www.youtube.com/watch?v=K7ikuayLl4I

They actually are! Synapse's 4K remaster is playing in a few places (festivals and the like), which will be released on Blu-ray some time this year.

And if that weren't enough, a long-lost uncut Italian 35mm print has been touring the States. It's coming to my area in November.