Were the Crusades Religiously Motivated?

A comment made by J. Stephen Roberts, mediaeval historian and host of Real Crusades Historyon YouTube, whose videos I've been sharing.

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One comment I constantly encounter running this channel: "Oh, the Crusades? They had nothing to do with religion! It was all about wealth and power, religion was just a cover for that! Lol!!!!!"
It's one thing to be ignorant, but there's an added cringe element when you think you're being clever. People who believe that "religion was a fraud" in the Crusades are not only incorrect, but they're showing themselves to be completely unaware of the current state of Crusades scholarship. For decades now Crusades historians have been pointing out that religion was a fundamental motivating factor in the broader Crusades movement. This earlier 20th century idea that religion was a giant fraud all through the Middle Ages is delusional, not supported by the sources, and anachronistic. This came up with my recent documentary on the Teutonic Knights. Some commenters just couldn't understand why I was discussing religion in that documentary. The undeniable historical reality is that the Teutonic Knights were intensely motivated by religion. Yes, they also wanted wealth and power, but they wanted it so that it could serve their religious order. These were guys who gave up all their own wealth and freedom to become celibate warrior monks. Yes, they wanted power, but they wanted power so that their order could be powerful, so that the Christian faith would triumph. Religion was definitely a factor here. It's not like they were looking to date supermodels and hang out by the swimming pool. This modern delusion that all the religiosity in the medieval world was some kind of elaborate scam is utterly stupid, and if you believe that you're not familiar with source material from the Middle Ages. This is projecting our own world back onto the medieval era. People took religion very seriously in the Middle Ages.