What he does before joining the approach doesn't seem particularly relevant,
It is very relevant when you are looking for traffic on Final as you're turning base! Would you be looking through the roof for traffic on final 2000ft above the normal slope? Bugsmashers can do what they like out in the boonies but at a CTAF aerodrome, they had better think "well there may be somebody else out there, I should be as normal as possible".
When were the rules changed to permit straight in approaches?
Many years ago.