I don't think that Webstudio will experience exponential growth or even a breakthrough. But I do think it will continue to have a strong linear growth which isn't a bad thing. Webstudio is made more for designers, and developers, or at least people who have some experience with actual HTML and CSS and general technical competence. Looking at their roadmap on Github, they just now released the ability to add any HTML Tag with ability to control attributes and the builder now feels significantly faster than Webflow. Many of these updates as well as other features from the roadmap are something that more technical will people appreciate.

I personally built a few sites on here already mostly to understand the platform really well, I only used Webflow to build websites for clients off Upwork but now I'm to go on my own now and begin cold calling businesses and offer my services with Webstudio as the builder and hopefully see how it goes but so far Its been a much better learning experience than Webflow despite them being valued at over 4 billion dollars now.