Just to second Mario’s comment (which is awesome) and add my perspective from supporting platforms at Lenovo. Most of our platforms (with the exception of a couple of workstations) are now S0ix only.
We did dual sleep support with both S3 and S0ix as an option in the BIOS (with S3 as ‘best effort’ for users who didn’t want to switch) on our Linux certified Intel platforms for a few years - and it was a nightmare.
Sleep issues are hard - regardless of S0ix or S3 - so it more than doubled the work. We were certifying with S0ix (that was only what Intel were supporting and was the default) and then doing internal testing with S3 (but more limited).
We found many S3 issues would creep in with FW updates - devices would stop working on resume, system wouldn’t sleep properly and battery drain in a few cases were horrible. Getting fixes done took forever and we couldn’t delay FW updates for a sleep mode that was supposed to be ‘best effort’. Users were frustrated (understandably) and it was not a good experience for anybody. We were honestly trying to do the right thing - but it wasn’t working.
We made the decision to stop doing S3 support last year and to remove the option. Having it available just didn’t work well and I agree with Mario - we have to focus on getting S0ix working right (and largely it is - and when it isn’t we work on fixing it).
I know losing S3 is going to upset a few people - but it was a considered decision on our side and based on user experience and how to be able to deliver better Linux support more effectively. I think there are ways to hack around it but I suspect the cases when that gives you a better experience are few (and I’d rather fix the S0ix experience for those few cases on our platforms!)
Mark