Over several years of motorway commuting I have seen so many stupid things it doesn’t surprise me at all.
I am amazed that as more motorways were built that some form of instruction on using them wasn’t added to the driving test. A simple lesson by an instructor would be good. When my children passed they were given a lesson. Luckily the M4 was near so no big deal. Not as easy for many rural areas but worth the time. Westist Wales, Scottish Highlands etc are more distant.