The longer you are with the company, the longer notice period, starting from 4 weeks and can get up to 6 months.
You also cannot fire a parent of a newborn if you keep the single 20-something in the same position.
They could still notify employees, it would be the nice thing to do.
"You'll be laid off once we get approval from the relevant groups".
Of course, that disrupts productivity for these target employees for 1-2-3 months, so they won't do it.
I wonder if the hit to productivity to <<everyone>> is worth it.
Generally speaking European laws protect the employees more than the shareholders. You can't really just employ a lot of people when things are doing well expecting to fire them if there is a downturn. It encourages companies to be more conservative regarding hiring which can be both a blessing and a curse.
Well, you can, but not as direct employees. The usual way is to enter a service contract with a different company who hires the employees and assigns them to work on bigcorp's tasks for 100% of their time. If bigcorp wants to cut costs, they just let the contract with the other company lapse and that company can fire their employees on the basis of "my own economic outlook is bad because we lost the bigcorp contract".
Strictly speaking, forcing a worker out in these recent tech layoff cases is going to be difficult. I'd expect both in Japan and other countries there will be much more generous severance package offers for "voluntary" quitting. The majority of workers will way that against the reality of staying in a company they know doesn't really want them anymore.
Fun part: Sometimes you cannot chose who you fire, the age distribution in the company may not change so firing everyone older than 45 is not an option in general.
That "giving notice" is used in the message is because of some law (I forgot) that requires this time but also permits to actually block people from working as long as they are paid.
[1]: https://de.wikipedia.org/wiki/Betriebsbedingte_K%C3%BCndigun...