The keysend stuff is basically just a lighting nodes pubkey. Some people run their own nodes or Foutain and Alby run large nodes for people so you will also see a custom key and custom value that is just the users account on said node. For you it doesnt matter that much but you have the problem eve...

They're just standard Lightning nodes that use Keysend rather than Lightning Address/LNURL/Invoices to receive payments. Most of them (other than Fountain) are self-hosted and self-custodied rather than being hosted by a custodial wallet. Both Keysend and LNURL are ways to get around Lighting's req...

I have had this concern from very early on.