Full breakdown:
Crash N'sane trilogy (physical + digital) : 156k
Crash Team Racing (physical) : 57k
Crash 4 (physical + digital) : <48k
Yeah, those numbers aren't great.
Activision and Sony are probably scratching their heads at this one, as all the online metrics for this look strong. The announcement trailer was something like the #6 trending video on YouTube when it launched and is one of the most liked videos on the PlayStation channel. All of the follow-up gameplay videos have huge views and there was a GI.biz article mentioning that it was doing well on Facebook/Twitter, so I'm not sure if these first week sales numbers reflect a lack of enthusiasm or if other factors were dominant.
You do have to wonder why Activision decided to release this one month before next-gen, especially without any next-gen enhancements currently announced. Unless they have some sort of strategy whereby launch sales are moot, that just seems like a bad misread of the market. It does look like a missed opportunity to not have this as a timed PS5 exclusive title - having the sequel to the original Crash trilogy help launch your new PlayStation just seems like low hanging fruit to me.
As for the price, I don't think it's unreasonable for the game to be full price. The game has clearly had a lot of money put into it and is larger than all of the original trilogy combined. That said, this is going for about £50 to £55 physical and £60 digital. In comparison, Cyberpunk 2077 is going for £45 to £50 physical and £55 digital, TLOU2 launched at around £50 physical and is £55 digital; even Super Mario 3D All-Stars is currently £45 physical and £50 digital, and that's Mario, the largest and most prestigious platforming series. I'll give Activision credit for releasing Crash 4 at a higher price than all of those: that was a big balls move, but I'm not sure if it'll work out, at least at launch.
And to be honest, I'm not sure if a major price cut before Christmas (say, it drops to £40) will help them in the long term. When Spyro 4 likely comes out next year, they're going to have the same problem with customers balking at the price, and the same goes for the CTR sequel and should they decide to make a wholly new Tony Hawk game, that too. People became a bit too comfortable paying £30 to £35 for Crash/Spyro, and Activision are going to have to somehow retrain them to accept paying full price. There's not a rulebook to follow because there hasn't been a AAA non-Mario traditional 3D platformer in what must be over a decade, outside of Portal 2 I suppose. I'm guessing that other publishers are watching closely to see how Crash 4 performs, and whether there still is a market for this sort of game at full price.
Aside from those two major factors, I think there are various other minor reasons as to why the numbers are lower. NST was thought to be a PS4 exclusive at release, as opposed to Crash 4 where people are waiting and expecting for the PC/Switch versions to come. The microtransaction kerfuffle from CTR is likely causing some to hold off for now, despite the devs telling otherwise that they won't be coming to Crash 4. They addressed the latter in the State of Play video, so the initial reports of microtransactions appearing must have spooked them. Some of the younger demographics have perhaps moved over to Switch since 2017, the parents are starting to feel the financial crunch of the pandemic and kids are no longer sitting at home and have gone back to school.
I don't think it's all doom and gloom though. The legs on this title will be interesting, especially around Christmas, and upcoming DLC appears to have been datamined from the demo so the game does look like it'll have post-launch support. If Activision have managed to secure Crash in Smash, I think it'll do well on Switch whenever that launches as well.