It would be hard to watch football this year and come up with a different opinion unless you are just looking at the name on their helmet. Alabama isn’t great on defense. Probably the 4th best defense we will have played this year. They haven’t had a really good defense in a while. People thinking we should not start Will because Alabama is going to kill him must not want him to play at all for the rest of the year because Alabama is a middle of the pack defense (ranked 66th in total defense) and we have tougher ones ahead.
Football Outsiders has three team defense stats that account for things like pace and opponent which the completely flawed total defense does not. Alabama is ranked higher in all three than any team we've played so far. I admit I don't really see what the stats are showing when comparing them to Kentucky, but it's not hard for me to believe they're better than Arkansas or A&M. I'm not saying these stats are the be all, end all, but they are a reason to think Alabama's defense is better than you're saying other than the (non)name on the helmet.
However, they used to be #1 or close to it every year, and they aren't anymore. So I agree with your point that they aren't what they used to be.