I'm reasonably sure VLF and ELF are very much in use but it seems as though ELF was abandoned by the US Navy. The Navy does continue to use VLF though.
The damn downloader in MSFS is the most infuriating thing. In Canada on either of the main ISPs I too out at 40ish Mbps whereas Steam and anything else really does close to the full 500Mbps. It also only downloads sequentially, pausing to decrypt each tiny file. And the updates are huge so it takes a good long while to download 2+GB.
Plenty of startups works on impractical stuff. Not to pass judgement but the fact that startups are trying doesn't necessarily confirm validity. See wireless power.
So yes, some are good. I had an issue where Rogers decided my modem didn't meet their channel bonding spec and capped me at 75ish Mbps silently even though I was paying for 150 even when I changed to a new modem with more channels. Teksavvy wanted to roll a tech (no matter the arguments and speculation about Rogers being a bad actor) at the height of the pandemic (disadvantages of being a reseller). I ended up having to change to a higher tier then back to prove it was a provisioning issue that Rogers had manually put in by forcing a reprovisioning.
I have Bell fibe but keep Teksavvy around as an automatic failover. Not just for practical reasons but I would like to give them money for advocacy but can't really stomach the objectively worse connectivity (not their fault).