I strongly disagree. It is not semantic at all. Difference between a browser and a web rendering engine is huge. I am in a business of building a browser and although we get rendering engine for free, three years later and thousands of dev hours later, our browser is still in beta and half finished. [1]
Building a general purpose web browser is one of the most challanging software development projects. This may not be the case if one is cloning Chromium/Firefox where you get both the rendering angine and the browser app for free. If you are using WebKit, you are writing the browser application from scratch.
Thats not the argument though, and its a bit of a difficult argument for Kagi specifically because it appears to be based on webkit I believe? The argument is: lets assume Kagi uses a non-webkit engine and is finished and live on desktop today. How much work would it be to now run against webkit? What is your feature set if you assume you are not able to modify the engine in any way?
We have a desktop WebKit browser and the amount of work needed for iOS browser is astonishing. So much that we didn’t even start working on the iPad version yet after three years. macOS, iOS and iPadOS are like three different operating systems with completely different UI/UX paradigms.
But we are not a good example. Take Firefox or Chrome on iOS, teams with hundreds of engineers. They are terrible mobile browsers. They feel completely out of place on an iPhone. Not because WebKit is bad, but because building a good, native, iOS browser is incredibly hard.
I would argue that yes, its because of Webkit. I used firefox for years on android. It was great. I use it on iOS now. Its basically garbage.
To bring it back to Kagi, if I'm reading your FAQ correctly for instance, you would not be able to support firefox/chrome extensions on iOS since you had to fork Webkit. Now imagine you are a browser with over a decade of use and features that now has to target a static other engine. How great of an experience do you really think you are going to get out of that?