Some people seem to think new art and layout are improvements worth paying for.
Game designers have a different set of goals than those directly employed to market the game. Of course, everyone wants the game to do well.
A new layout in the books is not aimed at current players, but it has been created to help introduce the game to new players. Some designers, -- I am thinking of former D&D designer Kate Welch -- have been very critical of how difficult it is for curious potential new players to learn the game from the core rulebooks.
Micah, your posts are surprising to me. As Oofta has pointed out, you seem to think that others here are not aware that Wizards of the Coast is a division of a moneymaking enterprise, just as Paizo, Chaosium, FASA, and so forth are moneymaking enterprises. We are all well aware.
Yet, the game designers are trying to create the best game. Jeremy Crawford, for example, has mentioned in interviews in the Dragon Talk podcast going back for years (at least until 2017) that he has kept a running document of changes he would implement to both presentation of D&D and the rules if he were to get a shot at revising the game.
So, a 50th anniversary approaches, Hasbro wants to capitalize on it, the game designers have ideas they would like to implement and revisions and options already present in Xanathar's and Tasha's that they would want to incorporate, the graphic designers feel like they could improve the art, it all comes together. One set of ambitions (e.g. corporate) does not invalidate another set of goals (e.g. game designers or graphic designers).
In the meantime, the books and adventures published since 2014 were presented in a way that a change to a class or subclass or imposed condition (stunned, poisoned, etc.) really does not affect the adventure because the adventures already refer to the PHB, DMG, and MM in their text. So, the game design team decided to not alter the fundamental design principles of D&D fifth edition so as to make it unnecessary to reprint the adventures and setting books. That is, I would think, considerate of them since I grow weary of repurchasing the same or similar books with each new D&D edition.
There really is no need to endlessly litigate dissatisfaction here. People play these games to escape from reality for a time and to express themselves. Speaking for myself, coming to a forum to read about a hobby I have had a longtime interest in, it is a bit of a drag to endlessly read fairly facile and obvious critiques of the company. Not that you don't have the right to do so, but I thought I would share with you my reaction in case you are interested or care.
In any event, happy roleplaying everyone!