The big confusion is in the word
'Quality' If you mean clean straight Yew suiatble for a longbow that is entirely different from saying the actual properties of the wood are somehow "higher quality".
You can buy plenty of really "good quality" Yew on the internet really cheaply... but it's 300mm long and won't make a bow!
There are plenty of other factors which we just don't know... here are some that may or may not be relevant.
Yew may have been managed in plantations, if so it takes a long time to get a crop. Our native wood lands may have been full of gnarled twisted stuff whereas plantations grown close together in naturally occuring high altitude woods (where the trees all huddle together for warmth
) may have yielded close grown straight trees
Woodland was being maintained for hunting? Growing Oak for ship building? Being managed for charcoal for iron making? or cut down for agriculture?
Language is a tricky chap and people will interpret the words to suit their own purpose. We should try and apply scientific rigor to what we say.
Note my prolific use of the word 'may' I don't know the answers, but at least I know that I don't know (drifts off into that famous Donald Rumsfeldt speach about the known unknowns and the unknown unknowns)
Your ability to leap to unsupported conclusion is still pretty breathtaking. The 130# Yew bow I just made could easilly have been a 150#, I had trouble getting the weight down, it the quality of the wood was so bad, I'd have had to make it bigger than MR dimensions not smaller.
You are certainly right about the current Italian Yew ... what I've seen in the flesh and on the internet is V similar to the English Yew I've used, and some has paler wood of lower ring count.
Del