What lasim does is allow you download your account settings. That's all. So your subscriptions, block lists etc. It doesn't allow you to transfer posts/comments so yes, your points will be zero on your new account.
If you admin a Community, you can't transfer that automatically either.
Lemmy doesn't display your score anyways except for individual posts/messages. Atleast not the web view.
I truly don't get why it matters. On reddit I made a new account once a year or so anyways and on Lemmy I've got like 6 of these. I never paid any attention to my or anyone else's karma either.