I suspect the average non-aviation-aware pax would see the 737-300 and 757-200 as being up-to-date, certainly compared with the 737-200. At least Jet2 spend a fair amount refurbing the interiors. Then it's down to good (as opposed to just statutory-minimum) maintenance and watching out for cracks. There are plenty of 20+ year old a/c around, and a good few years ago I regularly used to hop onto a/c that were older than I was, even as an adult! Admittedly they were Viscounts

I think Jet2 have been shrewd in their fleet acquisition policy; they are consistent and not just bought in any old junk (the 146 excepted and I can say that as I used to sell them

). If they step up to the 767 (and I have no inside knowledge here) then again the pax perception will be of a modern a/c and doubtless PM will source some from someone desperate to offload for financial not technical reasons. As a local I just wish the colour scheme was blue, white and yellow rather than the dreaded red and white