Yeah, they know they are doing though, they are aiming for those that work 9-5 have life and kids and some spare changes and milk them hard. Like this game would take 200 hours to complete fully with X hundreds of hours of post game content that was designed to make your grind, but you can also pay for this [xp booster, resource pack, legendary set, etc] to make sure you can enjoy the post game content if you don't have the time to grind the game how it's "meant to be played".

In my AC:Odessey example, I think at one point the designer might be doing a heavy zelda influenced where you just pick up stuff enemies dropped and the blacksmiths are there for you to repair items broken as resource dump. (which make sense and very fitting of that era and how resource would work) But once that MTX department put their finger in now you have a derailed system. There is a spread sheet that list the hours required to upgrade a legendary piece to which level, and recommended level to get them(as their starting level is fixed and not like the enemy droppped item that matches your level), I saw the numbers and downloaded the cheat engine table the next hour.