That's a different discussion than the question if regular flu seasons can overload the healthcare systems. Yes they can, and we regularly underestimate them.

And I'd actually also disagree that this is 'nowhere near as bad' as COVID-19. In countries like Germany or South Korea the death toll with high rates of testing appears to be somewhere in the 0.2 - 1% range. That's something I would argue is a difference in quantity rather than quality, with the dangers lying in the aggregate disease burden and vulnerable populations in particular.

Something I meant to say upthread slightly and didn't:

It seems like the nature of the overloading is different.

In particular, from those reports you mentioned, it doesn't seem like staff had to decide which patients to treat or not.

With COVID-19 we are hearing reports of some patients not being treated because there is not enough capacity (either staff or equipment) and so the death rates can be very high as many people receive inadequate treatment.