there were some people opposed to running all the gen 7 formats as a good bit of that playerbase has moved away from the game and many newer players started in 8 or 9. as such we decided to cut 18 from the pool since it just had the spotlight ladder and a few tournaments ran for it.Hello, why not VGC18? LOL
Quite a few people agreed that 3 gen 7 formats was too much, as you can see in zee's post (https://www.smogon.com/forums/threads/vgc-classics-pl-iii-general-talk-thread.3769059/post-10660082)VGC18 and especially VGC16 are missing lol.
And for the rest pretty much no one commented on it but also barely anyone/no one included it in their personal "ideal format list" posts2016 sucks and so much of playing that format was memorizing gameplans. That’s one of the worst experiences in a retro tour. Ideally you can pick a team, play a few warm up games, and go battle. That’s not effective in 2016.