Now I'll have to look up info and photos about Championship stadiums :P There certainly aren't stadiums larger than Amsterdam Arena and Der Kuip and fans there are pretty awesome too. But if you go outside to the top few clubs, the Championship tends to have the larger stadiums than the Eredivisie. Roda JC play at a stadium with a capacity just bellow 2000 while Burton Albion's ground that is the smallest in the Championship holds just below 7000.
It makes sense that there would be some really nice grounds with great supporters there, too with historic clubs as Villa, Sunderland, Sheffield W and Leeds.
Where are you from and which team do you support?
I'm still keeping my possibly unreasonable undisclosed location policy here on steemit, but can tell you that I have no real personal connection or bias towards the countries mentioned in this thread. Also I wouldn't say I support a specific team in particular nowadays. There are multiple teams I have sympathy for and I just want to watch interesting and exciting football played by technically and tactically astute players managed by smart and inventive managers. Stadiums with atmosphere and history are also something I enjoy.
The league I follow the most is the Premier League (as it's the most interesting and competitive and currently has the best managers) and I also try to keep up with the Bundesliga, La Liga and Serie A and to a lesser extent Ligue 1. And of course the Champions League and some Europa League.