Surely the clue to IQOS is in the registered name: I Quit Ordinary Smoking. It's smoking but different
They heat the tobacco not burn it and yes it gives off much less nasties compared to a regular Malboro but as the FDA put it "According to the applicant, 54 HPHCs are 54-99.9% lower in the IQOS system"
That's still potentially a worrying amount of Harmful and Potentially Harmful Constituents (HPHCs) than vaping. The formaldehyde for a start is one I'd keep away from
If I were to take up nicotine again I'd go with Nick's vaping over IQOS 99 times out of 99
It isn't smoking...

...because there is no smoke.
It heats tobacco, produces some vapour which smokers seem to find equivalent to smoking real fags.
And even if it is
only 54% better than 'real' smoking and (according to you)
and up to 99% better than real fags it is significantly better than smoking real fags or spending £££££s on vaping (yes Nick, we're looking at you) and going back to real fags... is it not...?
Vaping works for some but not all (LL included) so IQOS provides an excellent solution. It produces (according to you) up to 99% less Potentially Harmful Constituents and LL hasn't had a smoke of a real fag since she got it...
Apart from you arguing against it in your OP (and probably never giving up

) what really is there not to like about it...?
54 - 99% less harmful. Cheaper than real fags. Smoke anywhere. Less offensive than vaping (no clouds of vapour)

?