AFAIK, all the 8TB drives were helium drives. AFAIK, the 8TB red drives came out Q1 2016 and I bought my first helium drive almost 2 years ago. HGST had 8TB helium drives almost 4 years ago and first announced (and I assume released soon after) helium HD's in 2012.you've never owned a helium filled drive in 27 years, certainly not longer than a year
every hard drive you've owned has been exposed to regular air with filtered breathing holes for pressure changes
there is near zero long term consumer experience with helium filled drives and what actually happens when the helium slowly leaks out after the second year
at $130 I had to try it myself though, I plan to get another in two year to clone it regularly
IMO, this isn't new technology.