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Re: #2, that is active sonar, which is for useful for locating objects that are silent, e.g., rocks.[1] It also is very loud and disruptive for whales and dolphins.[2]

[1] https://oceanservice.noaa.gov/facts/sonar.html

[2] https://skeptoid.com/episodes/4236

Ah of course, the issue several years ago when the Navy's testing was causing whale / dolphin strandings...

I was a sonar tech on a nuclear submarine 20 years ago. I don't recall hearing about any ultrasonic applications. As for the "audible ping": Yes, such a capability exists, and it is very much like the movies. It is rarely used for the reason you mentioned.

1) Yes, it’s nicknamed “Gertrude”.

2) Yes, every tactical platform that hunts subs has an active sonar capability of some kind. (Hull mounted, towed, dipping, sonobuoys, ...) When the ambient noise floor exceeds the target sub’s noise, you need that option.