OK, take this in the spirit intended, and not as the semi-angry diatribe it could come off as.
First, STEP is under no obligation to 'inform the ignorant'. The FPS issue with Havok has been a well known and documented issue, dating from the original release of the game back in 2011. There are a large number of similar things, none of which are mentioned in 'large red letters at the very start'. Most of these are easily searchable, easily corrected, and not in the scope of the guide to correct. These have nothing to do with modding your game, they have to do with running your game.
Second, and following somewhat the last point, they are also under no obligation to maintain anything. There are, to my certain knowledge, a grand total of two people who still work on the STEP project on something resembling a full time basis (and one of those, I'm not certain of). In the time since 2.10 was released, if you had read around these forums (and especially in the announcements) you would note that there has been a LOT of work going on in the background to bring in a new site, a new content management system, and a completely updated STEP 3.0 for Skyrim LE. This milestone is approaching fairly soon. What you consider 'reasonable' was not possible based on those two things alone.
STEP is not intended to address 'broader issues', as it is now and always has been a 'Vanilla +' type guide.
As to your concern about mod count... Take a look at Lexy's Legacy of the Dragonborn: Special Edition sometime. It's well over 500 mods and 100 GB of downloaded mods cobbled together. You are in NO danger of anything there, unless directions and best practices have been ignored.
I get where you are coming from, but I would advise you to be more informed about things before you start throwing things out as you just did. While I know you don't intend to be negative, it's very hard to see your statement as anything but. I again remind you that this project is maintained solely at the discretion of TechAngel and Z. The fact that this guide is still around is a testament to it's flexibility in the face of time. It is known that STEP 2.10 is not current - there are numerous threads on this forums that talk about this, with workarounds and recommendations associated. I'd recommend doing a search or taking a look around.