I really don't understand the purpose of music streamers, can someone help?

Hello all

I'm newer to the 'audiophile' world and have been learning a lot. The one piece of equipment I cannot understand is a music streamer like the wiiM and similar.

My current set up for streaming music (I just use Spotify at the highest bit rate) is a google TV device plugged into my TV via HDMI which is then connected to my integrated amp via optial cable so the entire chain is digital until I get to my amp's DAC. Is there any substantial difference in sound quality or anything with my set up compared to the WiiM or similar?

The only situation I can see a streamer being relevant is if someone has a hi fi set up in an area they don't have a TV and they don't want to hook up a computer (I also know you could use your phones Bluetooth but I do acknowledge that does introduce some unpleasant signal compression) but that seems incredibly niche for how popular streamers seem to be and how expensive some of them can get. Plus I feel like if it's a matter of sound quality spending the money on better speakers / amp/ subwoofer ect would make a much bigger impact.

Thanks!

Edit: Some people asked what Google TV device I'm using and it's this:https://a.co/d/aKPcxpp