alt Hacker NewsFor most non-technical people this is irrelevant. Even if the router supported OpenWRT, they wouldn't know how to install it, let alone how to configure it.
Luckily, many (but certainly not all) continental West-European ISPs allow you to lease a Fritz!Box or you can buy one in a store and hook it up [1]. Perfect router/modem for consumers (not too complicated), can be configured through a web interface, and the hardware and software is developed by a German company.
[1] Many European countries have router/modem freedom, so an ISP cannot block you if you want to hook up your own gear. E.g. quite some tech people here use their own XGS-PON fiber ONT or at least their own router + modem.
The British ISP I tend to recommend gives you a Frtizbox (included with monthly package with 12 month contract, but becomes your property), but most will include a router with their package, usually a rubbish one, and most people do not care about having a good router.