As a person who personally enjoys Master Mode, I can say that in some cases, it's not necessary to make a large number of changes in a game to make difficulty enjoyable.
Though the claim of bloated stats, with little else gets thrown around often, I can say with confidence, that the fight with Queen Bee, Wall of Flesh & The Mech Bosses are all noticeably different IMO.
- Queen Bee, her dashing/ ramming attacks feel faster & seem to require the player to react quicker or to anticipate her next attack, as in some circumstances her attacks are unreactable.
- Wall of Flesh, this Boss will pretty much steamroll you at an obnoxious rate of speed. I actually had to build a bridge to win, as it felt impossible to beat him without one.
- Mech Bosses, these fights were always a decent challenge, but now, any mistake you make will likely get you killed. If you somehow get attacked off-guard, winning feels impossible.
- Betsy & the OOA, this entire event will have you on the edge of your seat, no mistakes allowed...
- The Pillar Events are insane!!
This is just the differences I noticed when fighting Bosses, but there's a whole lot of game to consider between Boss fights, which also has a huge effect on how Master Mode feels to play; things like Invasions or Events are a great example. It's also important to note that the free, extra Accessory Slot afforded to you from the very beginning, is very fun & allows more flexibility with certain builds; it's actually hard to go back to Expert Mode because of it...
...either way, I can totally understand most players disappointment, but I do feel at times the failings of Master Mode are greatly exaggerated. The unique items alone would've sold the Mode & it's not like new content wasn't added to make the experience slightly different than what players are accustomed to.
- Some of the newer Mounts are super fun, for example the Mourning Wood Mount & Witch's Broom are hilarious!
- The new Trophy/ Relic Items are gorgeous & a nice, new furniture item to add to your collection (try making a Trophy Room now, it looks great)!
- Depending on your progression, using buffs & Potions feels necessary now, before they were kinda just there IMHO, if you wanted training wheels.
There's defiantly incentive to play Master Mode, as it's
somewhat Expert Mode +Ultra. If you already like Expert Mode, there's really no reason to dislike Master Mode, other than principle. It's objectively more difficult & contains exclusive content. Nothing about it felt artificial IMHO.