(Edit: ah, no, I see: the next steps are quite dark-pattern pushing you towards the app. Yeah, that's quite shitty)
The only point I can see here is that once you are in the app it keeps encouraging you to use it and doesn't keep suggesting you might like to use the online portal instead. But I don't understand the initial premise about not using app stores. If the author didn't want to use an app store, why did he download an app instead of going to gov.uk?
"The easiest way to apply is on the app"
"By applying on the UK ETA app you're more likely to: complete your application quicker; get a faster decision".
"You should apply online if: you cannot download the app on your phone; the person you are applying for is not with you"
All of these are things you see over the course of the THREE (!) pages between https://www.gov.uk/eta and the actual start of the online form, https://apply-for-an-eta.homeoffice.gov.uk/apply/electronic-...
It really gives you the runaround and makes it very clear than the non-app flow is a weird, second-tier option.
>> It's really not that many hoops
> That's... What the article is about
I have no idea what you're trying to say here.