I was surprised to read the label on a GoPro battery and see it rated to 4.4v or thereabouts.

I used to build quadcopters around 2015, and some of the battery mfgs released "LiHV" batteries, which were supposed to be safe up to 4.35v, however if you actually charged them that high, they would puff up like balloons after only a couple flights. Maybe with the cumulative advancements in the last 10 years, they've been able to push up the max voltage more safely.