The State of Web Design in Linux
It pains me to say this, but unless you're someone who's working with an existing CMS or can comfortably work with a text editor or one of the editors above, you're not going to find the volume of newbie friendly software tools for web development in Linux. The only Linux friendly web editors I see getting any attention at all, are those designed for more advanced users.
The reason newbie web editors continue to stagnate isn't really that surprising. The masses are moving to web-based alternatives. This is especially true with the expansion of new developers opting for solutions like WordPress over that of simply running a static website. The idea of running PHP and databases is suddenly easier than it once was.
I think the last piece of the puzzle is with cross-platform "site-builder" type tools available from companies like GoDaddy among others. GoDaddy's Website Tonight allows even the newest webmaster to hit the ground running and as a result, feel like the need for installable software is unneeded. Bundle the revelation above with the fact that advanced users are generally quite happy with a text editor and a Sunday afternoon, the need for tools such as Quanta Plus among others, seems almost silly now.
So coming full circle back to the original question, yes, I think that with the advances made in web-based solutions and the maintenance provided on advanced editors, Linux is perfectly suitable for anyone looking to build their own website. They key I think, is to research the right tool for the job first.