Unintuitive interface, does not mean bad. Means just TeXmacs is different from other software (like LyX) for example. But the interface is well thought and carefully implemented. It requires some time to get acquainted but then you can do many things are not possible with other software (like shown here: https://www.youtube.com/playlist?list=PLjXdYclFpynD0ufg_pp-5...) And is not dead. :) We are a small number of developers but the software is used every day to write academic papers with a lot of math from a very affectionate user base. If LyX works well for you no problem. But you should give it yourself some time before making a judgement. It is surely very different from LyX.