>>322758
The problem with that would be twofold- the first, how a staff is composed for a video game. Since most video games are group projects, with roles varying wildly in both effort and time, you wouldn't be able to hold everyone to the same schedule. It'd require an awkward amount of perfect communication to slap everything together without a hitch. Then, like I said, not everything requires the same amount of time, or can be completed at the same time, either; you're not going to have your concept artist and your QA team working at the same time because those are involved in two very different stages of production.
The second problem, is that it only gets more complicated when you get to AAA games, because then you have entire teams working on multiple projects at once- you can't afford to drop in on a set schedule just for one game, because you have three more you've got to complete your role in. So you try to focus and clear one all at once (long hours) so it doesn't come back to burden you later on a different project.
Another issue would be budgets. Outside of subscription games like MMOs, you'd be hardpressed to keep paying your team to show up 9-5 continuously through the year, especially since vidya finance is quite wonky- In a 'good' setup, you might have an influx of cash to start with (say, invested from a previous profit, or Kickstarter), maybe a little bit of cash from preorders, and then whatever you make selling the game. It's not a 'steady' amount, like other business, who can expect (x) amount every month/period/season. You get 'this' much money to work with and God help you if you run out money before the game is done. So to cut on unnecessary costs (and wages), sensible teams will work increasingly harder on a game until completion, only having the relevant staff on hand. (Again, you won't need your debug staff on board at the beginning of the game's production, or the concept planners at the end of the game's production.)
9-5 models are for businesses and companies that have a relatively stable flow of cash in and out. Video games are quite often make-or-break, requiring but a single fuck up for the community at large to crucify said game and result in piddling sales- and therefore, no profit. Games can't sustain a 9-5 model outside of the largest companies working on multiple titles at once- somewhere, where they have a 'safety net' of games to fall on in case one project goes awry. (Often times, you see this in the sense of 'yearly games'; Battlefield, Madden, Mario, Final Fantasy, the like- flagship series that can support a company even through fucking up something else.)
It's just basic entrepreneurial skills and logic, especially when it comes to independent devs. And that's why you see such an outcry from the usual suspects; being an entrepreneur requires effort, a fair sense of risk and reasoning, and above all, the ability to break away from conventional business management, including things like cushy 9-5 schedules and regular paychecks.
Some indie devs don't want to put in that effort, though. They'd rather much prefer to receive a cushy steady income from Patreon while putting out as little product in as long of a time frame, because it works. Look at Literally Wu; how many years has it taken to put out a game with PSX graphics and a port that, last I bothered to check, never happened? And spends most of his time shitposting on Twitter instead of doing actual work? And keep in mind he gets paid for this via Patreon.
The idea of 'crunch time' horrifies these kinds of people, because not only would they have to get work done, they'd have to do it in a manner that doesn't drag it out for several times more paychecks than they should get for that amount of work. Getting paid for work, not time, is a real pain in the ass when you've build your life around the latter.