DISCLAIMER: These are just my initial thoughts, I am fully willing to alter my views if there's a good discussion, and I don't claim to be an expert; just a regular player the same as everyone else.
To me, it looks more like the buildpath of marksmen was changed without actually fixing the problem of them being near-mandatory every game. I am very skeptical these changes will cause non-marksmen bot laners to become a norm, which was the initial goal for midseason. They are still going to be the most consistent, reliable class with the highest DPS. There are still no real competitors to them. Fighters? There's too much counterplay for them; those armors nerfs don't mean anything if you're never going to have the chance to actually hit the adc. Mages? The base stat changes are actually WORSE for mages, because adcs lost armor (which means nothing to a mage) while gaining health.
So, I can't help but feel they just gave up introducing non-marksmen to bot lane and moved on to other goals.