I know Sims 5 isn't coming out for years, so take my negative perceptions with a grain of salt. However, that preview didn't really impress me.
The build mode looks more advanced, so I guess that's nice for builders. However, I'm afraid the game will cater specifically to builders, like the Sims 4, with the sims and their personalities left by the wayside.
The idea of a game compatible with mobile sounds....questionable. How many phones would even be able to run this game, and how much battery and graphical power would that phone need? And, like some others have said, it's possible they might have to limit the game in order to get it to work properly on everyone's smartphone.
Multiplayer and "collaborating" with other simmers does not interest me in the slightest. I think they're leaning very heavily into making the sims a competition. I wouldn't be surprised if there are timed challenges in game, where you have to build the best house or have your sim gain an achievement to earn simpoints, which you can use in the new Sims Store.
I think it's very likely a Sims Store will make a return, how else can they award simmers for completing multiplayer challenges? I wouldn't be surprised if there are also paid mods and cc as well, along the lines of Bethesda's Creation Club.
I think the main attractions for the Sims 5 will be its multiplayer aspect, build-mode and mobile compatibility, and none of these interest me at all.
But, we'll see how it goes, the game still has years to go.