they certainly aren’t, and given the print run sizes of WotC, they become a rounding error (as opposed to for an indie publisher, same effort / cost to create the book, but 1/100th the number of books)
Another thing to keep in mind is that not all things are affected by inflation equally. If gas and rent goes up but everything else stays basically the same, there is little reason to raise book prices. If paper and printing color prices go up, there is.
So the price increase being in line with overall inflation does not really mean anything, esp if half of inflation is greedflation to begin with, ie companies raising profits instead of offsetting rising costs.
Also, number of pages keeps going down while the prices stayed the same, that is also an ‘invisible’ price increase. If Amazon is correct, Glory of Giants is 192 pages, when we are used to 224, 256, or more in some cases.
The new core books should reverse that trend again, but it shows that books are not really priced based on manufacturing cost, otherwise a book with 200 pages should be cheaper than one with 300.
Finally, this will be the new price point for some years, so it has to factor in future inflation as well and kind of average it out. I.e. they make more profit now on $60 books than they will going forward, as future inflation will keep chipping away at the profits.
So there are a ton of factors here the ‘the price increase is in line with inflation’ line ignores. This is not just a matter of bringing your current profit in line again, and it could have waited some time too, WotC was not exactly struggling because of inflation. They saw an opportunity, they ceased it, it could have happened a year from now just as well, it could have been a smaller increase. Ultimately this is not about the price WotC needs, it is about maximizing profits, it always is.