That pop-up should be easy enough to resolve yourself.Tracking cookies and suspected tracking cookies aren't necessarily threats but they sound suspicious. Use FF and set it up to remove cookies upon exit or add trusted sites as you wish to keep those cookies that are useful for you..as those that remember you as a registered user, your banking institution etc. The diagnostics look at that and predict the hard disk is going to fail using SMART.
You go to the dentist for a prophylaxis & checkup and they want to "up-sell" you on filling a cavity.It's gonna happen cuz that's part of the experts' job, to test and evaluate.If you think you know more than the expert, then clean your own teeth.Computer techs at that level are educated at tradeskill/community-colleges or military.On the one hand, there's prob'ly a reason they didn't go pre-med or MBA.Yes, the unaware can be taken advantage of and can't prove one way or another that a vendor is being completely honest. You may not have SMART enabled but they would look there.