Welcome!
I'm 72 and use my 2012 MBP 13-inch about the same amount. Small world! It is my backup and travel computer, so it hasn't seen much travel since COVID.
I've owned mine since mid 2013 and simply close the lid to force sleep when I am through using it. It is healthy and the original battery is still running strong, knock wood.
I suspect the opinions about "leave it open when sleeping" are due to concerns with the computer heating while asleep and the lid trapping the heat. I have never detected any heat at all after mine sleeps. The keyboard and display are room temperature when I open it.
I believe that idea is a hold-over from the earliest MacBook Pros, whose lid switch was not reliable at keeping the computer asleep when the lid was closed. That oversight, which can make the computer super-hot, does not exist in the newer "Uni-Body" models like ours.
I do recommend restarting the computer every 10-14 days or so. If it has the original 4GB RAM, a restart clears out deadwood that can slow things. The occasional restart keeps things "limber."