Fellow glasses wearer here. You can get straps for your glasses to keep them attached. I also just put them in my pocket as I am about to bored (my pockets always have a zipper or button)
This is what I use and I have ridden Velocicoaster about 10 times now with my sunglasses on, as well as all of the rides at both Universal parks and have never had any problem with them coming off.
Eye Glasses String Holder Straps - Sports Sunglasses Strap for Men Women - Eyeglass Holders Around Neck - Glasses Retainer Cord Chains Lanyards https://www.amazon.com/dp/B07T2WBVDB/ref=cm_sw_r_cp_api_glt_i_H5DV96G1JCNEXKYFBNHW
NTA. Get him some of these for Christmas