I feel like The Internet has this urban myth that says keeping a charged battery plugged in all the time will eventually cause it to explode and burn your house down, guaranteed.
I get that keeping a battery at 100% charge is not great for it in terms of longevity (ability to hold a charge). And it's obvious that heating the battery up by running the laptop at full tilt inside a backpack or something will turn it into a spicy pillow.
But I struggle to imagine the failure mode that reliably shows up when keeping the laptop powered on 24x7 that is never a problem for 8-16 hours of continuous use while plugged in (a very typical work day for my laptops).
I ended up repairing the Mac, replacing the battery, and installing Chrome OS on it. (chrome sucks though, someday I’ll get it back out and switch to real Linux)
I had a MacBook Pro where the laptop worked but the battery became swollen so much that it distorted the case. If I wasn't there to notice it, it would probably burst at some point and Lithium is very flammable.
It's probably rare and overblown, but it can happen.
If that had been in a closet, it would have been months or years before I realized.
for example some alienware and XPS models rely on the battery for amperage capacitance when their big onboard GPUs get busy; allows them to run cooler/less-wattage/smaller wall-warts but it also makes for a platform that'll crash when it hits a high GPU usage without a decent way to make up the amps.
'spose you could use a bigger power supply if you get bios/uefi to play nice. hard proposition sometimes with Dell products.
Batteries degrade much faster when fully cycled repeatedly, and even then just about any laptop battery can easily make it 6+ years with low-to-zero risk of failure.
Apple documented the behavior in a support note. I’m not sure if the Apple Silicon models do the throttling as well. I guess the situation doesn't come up as often since the batteries are no longer user-removable.