I'm sure Hasbro would be delighted to render D&D 'lifeless' enough to pull in the orders of magnitude larger player base & income stream of an MMO. But, it's really a meaningless comparison. TTRPGs and MMOs are both RPGs, but trying to paint one as better than another, when they're just different media, gets nowhere. Plus 'your RPG is an MMO' is just fight'n words since the edition war, anyway. It's like a liberal calling conservative policies fascist or a conservative calling liberal policies communist. Just a red flag waved in front of a bull.
Not really. If you present many options, some of which are substantially & strictly superior to most others, you are actually restricting freedom to create the characters players want, because only some of those options are real, the rest are non-viable 'traps.' If you present fewer options that are at least arguably balanced/viable, they're at least all real options. The same goes for tactical options, if 'rest' is a tactical option with many benefits, and 'press on' is a tactical option with no benefits, then there's not much of a choice, you rest unless forced not to - the crux of the issue, really.
Again, that's essentially destroying options, only, in that case, for the DM. Might the DM want to run a scenario where significant time passes between challenges? Yes. Can he, if his responsibility includes forcing balance on a party that includes classes with who derive radically different benefits from 1/24hr 'long' rests? No, because his freedom is being restricted by a need to compensate for
Can a DM make a campaign in which Brewing tool-proficiency is as plot-important as Thieves' Tool proficiency? Yes. Does it greatly restrict the kinds of scenarios he can use. Heck yes. Is that a good thing? No. But there's a way around it: don't 'charge' players as much for generally-Adventuring-useful abilities as for generally trivial ones. If Expertise in Brewing comes up twice (or even never) in the course of a normal a campaign, while Thieves' Tools come up virtually every session, you can afford to essentially let a player have the former 'for free' (or darn near it), because it's mainly window-dressing. It's worth noting, in this context, that 5e /does/ make it pretty easy to add languages & tool proficiencies without build/level-up resources, via downtime, so it's really only the insistence on layering Expertise on what is otherwise a trivial ability that's problematic.
Well, the rules structure certainly doesn't focus much on balance, and leaves plenty of 'balancing' to be done by the DM - inevitably so, with so many optional modules (with even feats & MCing being optional, for instance). Guidelines are, I guess, still not there. Early in the playtest we were 'promised' (not really, Mike made no promises, per se) crystal-clear guidelines in terms of the intended balance point of encounters/day. In spite of being a don't-hold-me-to-it not-really-a-promise promise, the 6-8 encounter day guideline did deliver on it. But, yeah, beyond that, there's really not a lot of explicit 'balancing' advice...
I suppose you could have a party Level calculation that's more in depth than just the average level of the PCs...? So a party that's mostly 3rd, but 'optimal' in a variety of senses, might be 7th, while a botched 8th level party could be 5th, that kinda thing...
...then the party's equivalent level could drop as the day progresses...?