I think we can safely exclude 'collaborative web design' applications from the set of hardcore tools not gaining much from being implemented as web apps for understandable reasons.
Huh? Why? Designers had previously been using native apps for ages — Photoshop, Illustrator, Sketch... Figma has been successful not just because it's collaborative but also because it's performant, powerful, and reliable. Not sure why you think that can't be achieved with other kinds of software
Ok, I see my point being not so understandable, after all. I didn't mean Figma isn't a hardcore tool, I meant that we exclude it because it specifically concerns with web technology (being a tool for web design) and leverages web to implement collaborative usage. So it's probably logical for it to be a web app.
You're still way off. It's not a "web" design tool; it's a visual design and prototyping tool. Folks are designing a lot more than websites and web apps with Figma.