This thread is very similar to another one I posted a comment on, it's a theme that crops up often, usually from slightly differing view points, but it always seems to go the same way! And ends out trying to compare the two methods!!
To get back to the original thrust of the post; WFP isn't going to kill the trade or the traditional methods of window cleaning, they are always going to be needed, ladder use is going to be affected of course, the writing is on the wall for that of course.
Fear of heights is only one of the factors stopping people start up as a window cleaner, you still have to go out and get hundreds of accounts, many will still look at window cleaning as being beneath them, or as a chore that they hate and couldn't bear the thought of doing all day long.
Setting yourself up with a ladder, bucket and a couple of scrims and a squeegee is always going to be way, way cheaper than investing in WFP, therefore those that will get into window cleaning because it is so cheap to start up are most definitely going to be put off by the extra investment of a couple of grand on a WFP.
Yes, you can go the DIY route and build your own system, most won't, they would want a ready made system.
And don't forget,they will still need ladders and all the rest of the traditional equipment, you can't get by doing nothing but WFP.
It isn't THAT easy either! There is a steep learning curve and a real skill to using it.
It could well go the other way, if people are forced off ladders there might even be fewer window cleaners, not more
Time to go! Work to do!
Ian