There are many things that Nostr has a deep impact on (none that would be understood by a 5yo, sorry!)

I very often find myself writing "Nostr's super power is X", but here are a couple that might resonate with you:

Endpointlessly:

Nostr makes it possible to create services without endpoints. Most software infra provides proprietary APIs that lock-in developers/companies into specific vendors.

Nostr allows for many integrations to happen in a normalized schema and publishing requests without specifying a particular party ("endpointlessly")

See NIP-90: Data Vending Machines for a quick read on this or watch this demo video I made a few weeks ago https://www.youtube.com/watch?v=OJx6ExVTS7c

https://github.com/nostr-protocol/nips/blob/5026747008c0a84c14079c39807296eebd409c36/90.md

Competition:

Nostr provides entrepreneurs a completely flat entry to build new services.

Whereas before entrepreneurs had to pay a tax to Google and Facebook for discoverability and remain at a complete disadvantage, nostr's organic data-types interoperability makes discoverability a solved issue for all.

All software offerings/clients stand on their own merit. I wrote about this this weekend on https://dev.highlighter.com/a/naddr1qqgrxwrfw5m8garwdvm85aenwajxgq3ql2vyh47mk2p0qlsku7hg0vn29faehy9hy34ygaclpn66ukqp3afqxpqqqp65wxtanuc