[PeterisP]

That's not something you need to worry about - if you have a vulnerable ssh daemon with a public IPv4 address, then it's already been indexed and you submitting / not submitting it won't change anything.

Scanning all standard ports of all addresses of all IPv4 internet is computationally feasible and is done by many parties. For example, https://www.shodan.io/ is one place that has done so and allows public searching of e.g. all public IPs returning a particular SSH version or having particular key exchange algorithms enabled.

[GordonS]

Not if it's running on a non-standard port though

[PeterisP]

Yes, non-standard ports transfer it to the domain of either somewhat targeted scan or serious effort - scanning all ports of all IPv4 requires many machines and/or many weeks, so that's not available to everyone. However, I'd still expect multiple organizations to keep an up-to-date scan of all public facing ports worldwide; it's impractical to do it for fun, but if have a need and some budget, it seems doable.