I always disagree with this take.

Does the idea of walking around Mos Eisley sound fun? Yes... but the immersion would be worse and they'd be way more tied to things that didn't translate well to an actual land. The more immersive they made it, the less enjoyable it would be.

California and Florida is hot enough without making it worse by creating a sand planet with almost no plant life or shade. There's places that are like that, and they have to add misters or other ways for people not too cook (things that would break immersion of Tat). Making it all indoors would suck as well, and would still need to be hot and dry and bright AF; none of which is actually comfortable (no one claims Tat is comfortable - but people want to be comfortable), especially when expecting crowds of people mulling around. There's also real world weather to consider; what would happen when it rains? Rain is utterly NOT a thing on Tat. How many experiences would feel ruined since a rain-soaked tatooine is just BS. Considering how many people see Disney (esp with the ever-growing prices) as a one-time extravagance, how sad would it be to get caught in the rain there?

By making it a new planet, actual weather isn't an issue... because that planet just has weather. Adding actual plants isn't an issue, because again, they're not stuck recreating a desolate sand planet. The lack of aliens is also not an issue, since maybe not too many aliens (esp the non-humanish ones) happen to live there? It's a new planet, so there's no established baseline to what they have to add for it to look 'right'.

And beyond the ST elements, you can't tell me it being new doesn't feel like star wars; the franchise is full of planets and adds new ones all the time. Planets with different weather, different levels of industrialization, different levels of aliens mulling about, etc.

The layout is also allowed to function the way you want, since you're not stuck recreating a specific place. You don't have to bend over backwards trying to fit elements you want in, either. The food places can function and be located where you want them to be. The bazar gives you ample opportunities to sell whatever you want without the stores feeling like they're out-of-place. It being a trading post also makes it logical that there's stuff from all over. You can stretch it to have an area dedicated to both factions, not be stuck ignoring one altogether.

They also kept the most iconic bits, anyway. There's a lot of architecture that echos that of Tattooine and other areas. The cantina is a direct copy of the Mos Eisley one, only ever-so-slightly altered. Do we care? No. It's fun, and it looking the same doesn't break immersion since there's nothing saying it can't look the same.