Absolutely! The numbers show they gain roughly double the sales with trailers/footage and no demo, they won’t budge until boycotts reverses that. Same with microtransactions we all hate; they basically just print money.
The reality is probably closer to the flightily nature of us as gamers - We mostly just want to try the game because some part of it seems fun, if that can be tried for free with a demo, why buy it now that we got our fix? Why would a big AAA take that risk?
The study was they tracked sales across multiple games for years, here’s the first example I came across in the wild from ten years ago: https://www.youtube.com/watch?v=us6OPbYtKBM&t=640s
Developer here - currently indie but was in the machine at one point. Cold hard fact is that demos hurt sales for AAA games, and pre-orders get cash in the door today to keep the lights on. With millions and years invested, they must hedge and limit risk as hard and as quickly as possible.
I personally agree with that sentiment. Rather than demos, I lean into cheap early access indie games that seem cool on steam, and use subscriptions to check out bigger games (humble choice and xbox gamepass). Tons of games to try, while still less than one “full” game in cost each month.