The monotonic behavior is not the default, but I would also be happier if it was removed from the spec or at least marked with all the appropriate warning signs on all the libraries implementing it.
But I don't think UUIDv7 solves the issue by "having less quirks". Just like you'd have to be careful to use the non-monotonic version of ULID, you'd have to be careful to use the right version of UUID. You also have to hope that all of your UUID consumers (which would almost invariably try to parse or validate the UUID, even if they do nothing with it) support UUIDv7 or don't throw on an unknown version.
But I don't think UUIDv7 solves the issue by "having less quirks". Just like you'd have to be careful to use the non-monotonic version of ULID, you'd have to be careful to use the right version of UUID. You also have to hope that all of your UUID consumers (which would almost invariably try to parse or validate the UUID, even if they do nothing with it) support UUIDv7 or don't throw on an unknown version.