I think in much the same way that your life has been touched by a murderer and it has influenced your opinion, if you were wrongly accused of a crime it would likewise have influence.

That being said, I'm sympathetic to your point here and I'm not advocating for eye witness testimony becoming the only source of truth. If I could somehow know for sure that this would ONLY be used for the worst of violent crimes it would soften my opinion, but I am very sure that the more normalized this sort of dragnet investigation becomes the standard of what "requires" it's use will get lower and lower.

If policing were entirely focused on violent and property crimes many of my opinions might change, but realistically I think we can agree that whatever investigative technique we are talking about will primarily end up being used to prosecute drug crimes, because that is much safer and more profitable for the police. Do you really want to be on a suspect list everytime someone thinks they saw a drug deal somewhere and you happened to be near?