I always thought Crozier was on the cusp of being a really damaging player. As Bizkit says, he looked best as an attacking half-back, but he never really nailed down a spot with us while were a very good side, and I’m not 100% sure he would be a first-choice player for us now.
The Bulldogs have us pick 40 for him in the trade, and in that draft we took High Dixon with that pick (or a version of it after trades). Based on the early reports on Dixon there is some upside there - and Crozier has managed to cement a spot for the Doggies - so you’d call it a good all-around result.
I don’t think anyone who has actually considered the situation could find it in themselves to boo. That said, there are some people who reflexively love to boo. They are more often Eagles supporters, but all clubs have them.