Couple things.
Apple first released a MacBook with a „Solid State Trackpad“ in 2015, leaving the MBP to catch up 2016. So that’s one company with two line ups. I haven’t seen any laptops irl that have a glass trackpad that weren’t Macs.
The glass DOES move, it can move A LOT too, depending on how much you press it. You can literally press the glass in the corners beneath the aluminium frame.
Debris and liquids can easily get beneath the trackpad or get stuck between the edge of the trackpad and the frame. Hand lotion is nothing but grease, which will slowly work its way throughout the bottom side of the trackpad if enough gets in, which it will if you do what OP did.
They do move and any kind of liquid or similar substance, ESPECIALLY if it doesn’t evaporate, will leave residue behind and may impede the trackpads performance.