Sure, but not every chimney/antenna/building in the country is fitted with those. Quite often it's just a straight ladder with no extra safety rails going straight up 100-200 metres. In that case the basic principles(clipping in every 2 steps) should apply - but like I said, are frequently ignored because of the time they would take.

Yes this is a huge issue. The solution really is to make safe ladder-climbing more convenient and inexpensive, so that people can and will choose to use it.

I do not do work-at-height, but my (unoriginal) proposal for a simple solution is to run a steel cable from bottom to top, anchored at both ends. This is cheap and low maintenance. Then a worker can bring their own cable-grabbing fall arrestor with a progressive-tear lanyard. Attach yourself to the cable at one end of the ladder, and climb up/down as you would normally until you reach the other end.