I wouldn't worry too much about people niavely purchasing 5.7 guns/ammo. The expense alone may deter many. It's not that big a deal or mistake if someone gets "sucked into" getting one. The 5.7 stuff will always re-sale to someone else.

I know a devestating case can be made on 'one-side' against the 5.7 round in comparison to 'other' calibers ... but that is the nature-of-the-beast regarding Caliber Wars. Many in the U.S. do not like its lack of terminal performance at conversational distances. The Europeans however designed it for effective military defense at longer ranges. It is what it is ...

There was a young southern gal who posted 'here' some years ago.
She bought a new FN Herstal Five-seveN pistol as (maybe) her 1st pistol purchase. I don't know how that one turned out for her ... She may not have been 'savy' but she WAS 'gutsy', for sure.

A lot of shooters really like the 5.7 shooting experience.
Fun, protection, high velocity, long range, accuracy, a different experience ... and they know what/why they are doing.