Originally Posted by
old,not bold
SNIP
But I'll predict that the assumption "if it's allowed to fly....etc" will prevail, not least because finding out in advance which type will operate your flight is well-nigh impossible, unless the airline only operates one model variant. This is equally true of customers booking through a tour operator.
I just booked flights on Air New Zealand. The seat allocation pages clearly showed which types were supposed to operate each flight, and distinguished between 777-200ER and 777-300ER, which mattered to me because of the arrangement of seats. In the other direction, I chose the A321neo, which meant a slightly different class of booking. People book online a lot these days, and it probably suits the airlines to get seat allocation done in advance. In these circumstances, it is possible to avoid an aircraft which is faintly dodgy, even if one recognizes that an exceptionally unlikely event is only made slightly less unlikely.