Yet another anecdotal data point, but I've done the same with my Switch and MPB. I've charged both from a battery pack, phone chargers, etc. in a pinch and neve

Yet another anecdotal data point, but I've done the same with my Switch and MPB. I've charged both from a battery pack, phone chargers, etc. in a pinch and never had any issues (other than really really slow charging speeds). I've just assumed those "warnings" are there for liability reasons because these companies didn't test their devices' charging capabilities across all possible USB charging devices.