Ok got it.I mean that as the caster levels, their lower level spells stop being strong enough to deal with the threats and obstacles of high levels. Especially since 5e spells don't getstronger as you level andtey share the same spell prepared limit.
So a highlevel caster will stop preparing Burning hands and Sleep and prepare utility spells like Chrm Person and Disguise Self. And they will use them liberally since they have nothing else to do with those slots (unless they are a sorcerer)
IME I don't see this because you run out of prepared spells and there are so many good 3rd level spells. Once I hit 6th level any extraneous slots are going to 3rd level spells. You don't have the slots to keep low level utility spells prepared.
Shield, Silvery Barbs and Absorb Elements are used a lot at high level by me and they scale really well IMO. Feather Fall is also usually prepared for me although not used as much. I usually have Disguise Self prepared at 1st level and 2nd level and drop it at 3rd or 5th. Charm Person is rarely in my book unless we find a scroll or something. At high levels though these (CP and DS) would only be prepared if there was some reason we were going to need it and we knew about it ahead of time.
As far as 2nd level spells, there are not many good ones to stay on the list. Tasha's Mind Whip, binding ice, Whiter and Bloom (which upcasts well) and on a bladesinger blur, but usually by 6th level or so I am only hanging on to two of these, or one if I find some 3rd level scrolls.