For what it's worth, I was down to one DC title (The Legion) during a couple years in the early 2000s, so they can lose me too.
Maybe "giant continuity plot holes" is an exaggeration, but it's been over a year and there's still a lot of confusion. Some of the Zero issues definitely helped with that but we're still learning about who these characters are now, and trying to figure out what, if anything, they used to be is still in tact. I think the 5 years thing was good in theory but it's just making everything feel squished. Especially with the Robins, which has definitely been a source of continuity bloopers, as well as the Teen Titans history, the Superman books were confusing. It also just seems that the more we learn the more people get upset.
And I was right about Whedon, and you quote proves it - the decision for Colossus to return was not Whedon's. The book needed something beyond just an awesome creative team to help continue its momentum, and that something was the return of Colossus... I didn't say it ruined the book, or that Whedon hated it... but he is on record as saying he didn't want to bring him back and cheapen his death.
Now, excuse me, I'm going to watch 'Slither'. Never seen it before. Hope it is good!