Is Mate 19.04 going to swap Apt for Snap?
No, snaps aren't ready for that yet. But maybe eventually.
Thank you. But I thought Ubuntu 19.04 was dropping apt? and snap will be doing silent updates in background like Windows
More apps are going to be installed as Snaps in Ubuntu (Gnome) with 19.04, but I haven't heard of dropping apt as anything but vague future ideas. The biggest reason I've seen for disliking Windows autoupdates is that you have to restart your computer. Snap does update automatically (you can configure it somewhat) but you almost never need to restart.
Ok thank you again. But silent updates with no control by user is a bit worrying.