Is it OK to use Apple's Magic Keyboard 2 and Magic Trackpad 2 Always Plugged in and Without Bluetooth

Title says it all. I am sensitive to RF radiation so try and limit my use of bluetooth technology. I have been using the magic keyboard 2 and trackpad 2 like this for a couple years, but recently the battery on my magic trackpad 2 swelled. Apple was kind enough to replace it to me, but I was wondering if maybe it was caused by me leaving it plugged in 99.9% of the time. For reference, it's plugged into the usb ports on the back of my thunderbolt display. I couldn't find a clear answer from apple online, and the guy at the genius bar said it's a good idea to cycle the battery once a month or so, but theres no way I would be able to drain the battery down to like 20% cuz the battery life is so good and I don't want to be using it with bluetooth for weeks on end.

Thanks and hoping I can get a clear answer that apple agrees with :)