I know when it was proposed and I know how stupid the arguments were by Brexiteers that doesn't make it any less of a stupid and awkward system, that realistically is going to have no benefit to the EU or any other people trying to enter it. I would've never been in favour of a system like this, I view these sorts of systems as a waste of time and money that could be better spent making going through passport control quicker and more efficient while still completing a high level of checks. Visa waiver is a lie, it's an E-visa that will make very little impact.
To suggest that there is no benefit to the EU is a tad ridiculous, they're not just coming up with this for the sake of it. The sheer cost of setting this system up will far exceed the income from the €7 they're charging for some time. However, the benefits elsewhere will be far greater.
As I already mentioned, you're standardising the checks performed on those entering the Schengen area. Every passenger goes through the same pre screening process no matter which country they enter from. That reduces the worry from countries where they may be concerned that others are not applying their checks in the same way, a physical concern in the case of the likes of security and a political one because of the perception from some citizens that some checks are lax. I'd probably suggest that's one of the reasons that the UK was also such a fan of it in the past too.
As the application is done prior to travel, it means that those who have issues obtaining their ETIAS aren't going to travel to the EU in the first place, unless they've then applied for and obtained a visa. That reduces the admin required at the country's border, as they either don't travel or are refused prior to boarding. There's also an economic benefit to the airline too, as they would be responsible for the return trip to those who are denied entry, so the pre screening would dramatically reduce that possibility.
You can only do so much to 'make passport control quicker' when you're not pre-screening passengers. There's a finite amount of staff you can realistically employ, a massive number of borders across multiple countries and a limit to the amount of space you can utilise. ETIAS allows for a number of questions/checks to be recorded before arrival, and
coupled with EES which will bring in biometric checks and removes passport stamping will make things quicker in the long run.
Finally, despite what you suggest factually this
is a visa waiver. It's a very similar process to what is already in place for the USA with the ESTA programme and it's a term that's very well established. Even the UK have one in place for some Arab nations, known as the
Electronic Visa Waiver which is being expanded next month. To obtain a Schengen visa takes at least two weeks, costs £68 and a tonne of paperwork. Having gone through other country's applications for work before - a quick 10 minutes to fill in a few questions on a computer with your passport details to hand costing £6 for three years is a far less involved process than an actual visa application.