Mustrum_Ridcully
Legend
Pun pun was white room, I am fairly certain we did Scry and Fry in some campaigns.Wrt that bolded bit the gm had a lot of ways to push back and put their thumb on the scale for each party member as needed by using things like body slot conflicts or magic item churn expectations. The "Christmas tree" was literally a bit of well designed gm empowerment with a dedicated behind the curtain entry about why the slots were so varied
Scry and fry(like codzilla) was more of a punpun adjacent whiteroom thing than something to see in the wild beyond perhaps a one off twist
And the DMG also contained a wealth by level rules and treasure guidelines, IIRC, and of course the DM can do whatever, including not handing out body-slot fitting magic items (though the default magic items in the DMG neatly fit really well to get your christmas tree going) and not have magic item shops (or magic item crafting) - but then, would the CR and encounter design guidelines still apply? What else does the DM then have to handle on their own without help from the DMG?
Though I admit, that was very theoretical, I don't think the CR guidelines and monster CRs were so neatly well designed that you could rely on them, there were plenty of outliers and your party's optimization created such a wide spectrum...