LG smart TVs caught logging audio with screen off and snooping on local devices
(www.notebookcheck.net)
The odds of finding a 4K 50"+ dumb TV (which is what it would take to be better than the 15-year-old but pretty high-end at the time 1080P 47" dumb TV I already have) at a thrift store seems... unlikely.
More to the point, it does absolutely nothing to refute my point that dumb TVs are entirely unavailable new at retail.