Unfortunately that is correct. You can use the Samsung Notes app in certain Windows 10 computers (Samsung ones) but that's about it. I miss the time when you could sync the notes to Evernote, but that partnership is long gone. Now all you can do when moving to a non-Samsung phone is to manually export all notes and transfer them manually either through a cloud service or data transfer.
That's why, even though the feature set isn't great, I've sticked to using OneNote for note taking now, since it pretty much syncs with everything.