To be fair, having the government mandate how much time you get off for working 40 hours a week is kind of just codifying the indentured servitude you're under.
What are you talking about? If the government didn't require paid leave, you might get ... none of it! So the mandate actually makes you ... checks notes ... less controlled.
That's only the minimum of paid time off though, and how many hours of a week you work is determined between you and your employer in the form of a contract. If you think that this is indentured servitude, to the state which provides you with taxes and services, then I really don't know on which planet and or reality you live in.
I still remember putting in vacation at my first job, three months in advance and they still said "well it's your job to make sure your shifts are covered". Fuck you, Karen, you make the damn schedule one month at a time, just don't put me on it that week.
Seriously. You aren't really managing your employees if they have to organize resource shortages for you. At my job, I tell my colleagues to just take time off and, like me, list a few close co-workers as people to contact in case of emergencies in their OOO reply. Nothing is life-or-death, so people can deal with waiting. It's not like anyone is taking off months straight.
What happens, if you are ill for a longer? You can't just work ethic an illness away.
And it's also stupid from the company's perspective. If someone has the flu and you have them come in - well - everyone will be sick and everyones performance will suffer.
Who thought this is acceptable, let alone a good idea?
Sounds to me that there wasn't anyone or atlesst not enough drivers for the Shinkansen, so it make totally sense in my eyes that the employer had to fix the schedules when it's employees weren't able to do so themselves.
Funny story, my wife told her boss she needed time off for our honeymoon as we drove to our wedding. She got it, but they teased her about it for a month.
Back when I worked a shitty retail job we would usually hire a few people on fixed term/fixed hours over the Christmas/New Year peak (ie, you get minimum 20 hours a week for 16 weeks starting November 1st), first couple of weeks are mostly training, then peak, then cover into the new year while the full time people take some leave.
Had one guy who got to the end of his training then informed management that he would need leave approved starting now and right through peak because his family was going to an expensive ski resort but that he'd happily pick up some more hours when he got back. Got really salty when he was told that that wasn't going to happen, and he was welcome to go anyway but shouldn't expect a job when he got back.
I would default to assuming that this is a professional job, so making sure you're covered in case something goes wrong is expected and also reasonable to expect from coworkers. If there's conflicts (I don't think I can support this while you're gone because I'm gonna be too busy with x), you go to your manager and ask them to figure it out. But by default, it's likely you know who is best equipped to support because they are already working with you.
As part of the team we all know, usually, the details of the projects we are working on, details that we cannot expect a manager to follow or know for each project, because there are a lot of details and many projects. A lot of them overlap in discovery, development, execution and deployment and also have different priorities.
And it is my understanding that managers also need to prioritize given sudden issues, emergency requests, and so on.
Anyways, with that info, we can decide who is the best fit for it given the experience they have had or not with specific projects.
Also it is usually not that hard.
You don't get a backup 2 days before your time off, indeed, more often than not, it is asked with a lot of anticipation.
Also, most of the time when you go on time off, you are encouraged to have all of your projects deliverables ready for when you are out.
That way, your teammates doing the backup are just checking in on the project and available for general questions.
Personally, I like to leave documentation as well for my backups so they know what to expect. It's not strange to have changes that imply more work for the backup so the extra context helps a lot.