The thing about sales in definitely true, Steam got rid of the flash sales during the big winter and summer sales which had the biggest discounts (although I think that's a good thing since that practice makes people spend more money due to artificial scarcity, but that's for another topic).

I think some companies have also hiked up their sales prices, one personal example I have is Yakuza 0: when I bought it a few years ago, it routinely went on sale for $5.99/€4.99, but now you can see on SteamDB that since October 2024 the lowest price has been $/€10.99. https://steamdb.info/app/638970/