Considering your spectrum I would not consider games that have planed multiple drops in a yeear as GaaS as that is schedule to finish. The thing with destiny and the like is they are planed to be for ever going. With no planed end the player is forever traped in an endles cycle to pay for the content of the month. On the first scenario you spend prbably double the asking price in small chunks, but the second is infinite if you get sucked in.
To answer your question then GaaS would be consider a game with no planed end where they can suck money from you by hooking you in.
Who done it good or bad? I would say that to do it good or bad is determined by the paywall. Games like Path of exile I say do it right cuz they add content thats meaninfull, not in a schedule weekly/monthly or whatever just to have something to keep you dosed up. they also dont charge for the updates and all their DLC is pure cosmetic. players achive everything by actual gameplay.
Now WoW I would belive is the worst ofender here. A monthly sub for a game in this date and age is just agregious. Destiny is another bad one as they make you buy the update as it comes out while at the same time having abusive microtransactions and time limited event where you are baasicly forced to pay if you are hooked.
So basicly like you said a bad GaaS is determined by if the dev abused the FOMO t extract cash from players and just makes it predtory. But a Good one not only has to not be predatory but also have meaninfull content update, even if not frequent.
Not faith in halo as 343i have a bad record and who knows about TloU. Buut I dont really have faith in any GaaS. Theres just to few gems out the piles of crap for me to trust the entire category of games.
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