You could create a DIY notification system if you want. In the past using a old Mac mini I had a script that would check new notifications from Lemmy rss feed if I recived an notification from Lemmy and then send a push notification to my phone using ntfy.

The script was janky it used apple script to trigger a apple short cut that sent the notification (sending a post request to ntfy).

I’m sure there is probably a more elegant way to do it.

Alternatively you could set up a RSS reader that polls Lemmy every so often to send notications.