I actually really liked the thing, hence it sticking around these 11 years since I got it. One thing I especially liked about it was that it initially just did the one thing. I went to a website or sometimes used an app, either in my phone or computer and pressed a button and whatever still image or video I'd been looking at on that source device, showed up on the TV I plugged the Chromecast in to.
Technically it still works, but it's getting harder and harder to do this simple task. It's been whinging about me not being signed in if I use it with YouTube and for an outrageously long time displays some kind of media control overlay that takes up a massive portion of the screen. That's what the phone or computer screen is for and the Chromecast gen1, not having been designed for this, is way too slow to do it properly so it struggles. It's increasingly difficult to actually get the cast button to appear even on Chrome on desktop, and there's some confusing shit to do with "web apps" on just about every website with media involved that I see no reason to indulge when the media plays without them anyway, but I assume that refusal has something to do with the damn thing not working anymore. Basically google have all but killed this device.
I see those Roku things as an alternative but that seems to be a full media player solution intended to essentially function as a smart tv in a removable stick. I basically just want a wireless HDMI input receiver that will work with web browsers or any media streaming service/app just like the Chromecast USED TO! Do they exist?
I want to be able to, without hassle, decide on a whim to send whatever media I'm looking at on a device, to the tv screen wirelessly.
It's basically an Android TV box (which as far as I can tell is just an Android device specifically for use as a smart TV) in the shape of a Chromecast dongle. I think you can probably use it almost exactly the same way you do with an old Chromecast and ignore all the apps (or at least install them once and then forget about them).
The hard part might be finding one, they've replaced it with a newer, more expensive 4K one so you might not still be able to buy the old (1080p) one from official sources anymore, but have a look and you might get lucky.