This is true. There are some major clients that have implemented it, but not many. I wonder how we can improve the situation.
Discussion
I've spent the entire day trying to figure out how to write and read from different relays in Nostrudel and Amethyst and it's an unstable, fidgety nightmare.
Amethyst has a very complex configuration screen for relays (lots of options) that took me a long time to feel like I understood what I was configuring.
I haven’t messed with relays in nostrudel.
You could try https://metadata.nostr.com/ which also has the advantage of backing all that up in case something goes wrong?