I'd think German traffic engineers could come up with a better solution, yet these are everywhere:
The bike paths themselves are desire paths for cars and motorcycles.
To block them off, they put up barriers, but those also block cargo bikes, wheelchairs and strollers, create a collision hazard, and force all cyclists to stop and dismount for no reason.
Of course, they'll be bypassed wherever possible – naturally by cars and motorcycles too, if there's enough room.
These are worldwide, they keep motorized vehicles off paths except for maintenance.
You ignored the side view, they can be easily traversed while on bike, I do it every day. But I love when the Internet second guesses engineers. Guess why these are on either side of a public road? Because otherwise idiot cyclists would not slow down and get hit riding into live traffic.
Unless the bike has a trailer, or it's a cargo bike, sometimes even mobility scooters may struggle.
Good luck getting a kayak through too, one of these means I need to take a pretty big detour when I want to go kayaking.
Cyclists seriously aren't a hazard, unless they're fat bikes. And this blocks wheelchair users.
I'm aware of their function. But they actively make the bike path worse for all users and block it off for some legitimate uses (wheelchairs, cargo bikes), that's why I'm saying there has to be a better solution. Like putting up blocking posts with a distance of ~1.8m on both sides of the path would be enough to keep cars from entering.
And if there's so little traffic on the road that cyclists don't expect it and slow down naturally, it might be a good idea to give cyclists the right of way at that intersection and design it accordingly.