Yes, if you simply suspend your laptop on most stock Linux distributions, then everything including the master key is still kept in memory. But Debian pioneered the (optional) cryptsetup-suspend addon. This issues a luksSuspend command which is supposed to wipe the key from memory, and on resume asks you to resupply your passphrase.
Up to kernel 6.8, this worked as described; starting with kernel 6.9, it silently didn't.
So you would still be asked for a passphrase, even though it's already available?
FYI: VeraCrypt is not the defacto encryption software for Windows.
I've been wondering why hibernate didn't work with encryption, because this seems like the extremely obvious way to handle it, but I have struggled to find anything about it for years - glad to hear it does exist!
But yeah, also rather obviously it's inherently a bit leak-prone. Though it seems probably pretty simple to test, just hibernate and scan all stored data. They could probably even do it on shutdown, as a hash of the key data would be sufficient to detect the key.