What about these notes makes them more tricky for clients to find?
They're not published to the "default" relays.
Depends. This one was orphaned to nostr.mom nostr:nevent1qqswu4rmrxu0ysc7rdl8rhxuk0yzh56rqnp2fptng56kl9gsa4jejmgppamhxue69uhk2tnwdaejumr0dspzqwlsccluhy6xxsr6l9a9uhhxf75g85g8a709tprjcn4e42h053vaqvzqqqqqqyeu4h7d