They can still have all of that for most of their users. Users that can't use these newer features should be offered a simpler more basic experience. Just because it's a minority of users that want to access your medical claims portal from abroad (who'd have guessed that this would be a valid use case for someone who has bought world wide health cover?) this doesn't mean that you should lock them out.

You are very short sighted. I hope you end up in a position where you need minor surgery in Vietnam during your gap year and can't enter the claim in the insurance companies system because they insist that ALL user must be able to see their fancy drop down menus with rounded corners OR not being able to book an onward flight from Cambodia therefore being refused entry because you can't prove that you plan to leave in the next 3 weeks all because the internet kiosk you're using is blocking the CDN that pushes some crap JS that adds nothing other than eye candy.

What's wrong with creating an alternate UX without all the overhead?

I hope you suffer the consequences of your own short shortsightedness.

Also, FYI, horses are still allowed on roads.

EDIT (can't reply) I think you'll find that medical insurance sites and travelling / booking sites are very similar and attract a very similar userbase. People book flights ticket and medical insurance, people fly then use the medical insurance when they have too. You seriously do live in a bubble, i have a feeling you are an American who isn't very well traveled outside of his own country and only uses medical sites in the context of your non state health insurance. You probably aren't the kind of person that would use any of the services I care about.

SECOND EDIT.. I spoke about my two target services from the offset and did not switch context. Do you not realise how these two sites / services go hand in hand?

I just got back from skiing. I used an airline site and medical insurance site for the same trip.