The system doesn't work very well so large numbers of passengers still having to be reprocessed manually - someone is making a lot of money selling a system that so far seems a bit shit. Michelle Mone of Schengen vibes.
The finger print screen is not hygienic - bring hand sanitiser for your fingers are going where hundreds of thousands passed before.
If you're married to and travelling with an EU citizen, the EU aren't allowed to count the 90/180 days thing against you and you'll get the ETIAS for free when it's introduced (a whopping €7 discount).