You can delete them from the command line. At least, you use to be able to. I haven't done it since they changed stuff around. Maybe nostr:nprofile1qqs0nt9skq6vfsgh06v979rrnuchau87mmnk2lqxpv2xaeusqfp30mqpzamhxue69uhky6t5vdhkjmn9wgh8xmmrd9skctcpzemhxue69uhk2er9dchxummnw3ezumrpdejz7qgwwaehxw309ahx7uewd3hkctc9ad278 knows how it's done, now?