The performance is better than it was at that time. At that time performance was the #1 item for improvement on their roadmap.
I currently pay for Notion and I don't usually mind the performance. However, things like opening a new window and changing it to a new document with the "quick" search (command-p) is still almost unacceptably slow (it's an Electron app). The benefits for me do outweigh the costs though.
I've never seen native apps anywhere in their stated plans.
Native vs electron is probably not the thing that makes notion slow - AFAIK (last used notion ~2 years ago) everything has to go through the web, nothing is local, and the performance bottleneck is their server.
I currently pay for Notion and I don't usually mind the performance. However, things like opening a new window and changing it to a new document with the "quick" search (command-p) is still almost unacceptably slow (it's an Electron app). The benefits for me do outweigh the costs though.
I've never seen native apps anywhere in their stated plans.