Web has been undergoing a swift change, and design tools have been lagging behind. This was one of the reasons for the tumult, when Photoshop started falling out of use for web design in 2008-2010. This started a huge race for a tool that would be suited for web design, with prototyping included. Adobe purchased, created, ditched a number of tools trying to fit the fast-changing market. FireWorks, Edge, DreamWeaver... Finally, Adobe XD, arriving in 2015, has more or less settled with the trend.
The idea is that the web design tool most not have the unneeded complexities that Photoshop and Illustrator have, being apps for photograph editing and print editing and vector graphics. Thus, a trend was formed that tried to cater to the realities of the web instead, combining text, vector graphics, effects available on the web through css, and some prototyping. Originally exclusively client-size applications, but then more and more cross-platform in-browser apps.
Figma one of those relatively new design tools, that allow to design for the Web with some interactivity. There are similar tools, like InDesign, InVision, Sketch, Adobe XD, Zeplin. These tools are specifically tailored for the Web. It's really exciting to see how the web design has emerged from graphic design, and how web design tools have progressed and emerged from photo editing software on one side, vector creating software, and print/layout software on the other side. The three sides, where different arts intersect in web design.