Actually although there are issues there are work arounds, yes they take time but they make the game playable.
Selling stuff: sell item (just one) flick to buy back tab and then back again, item has gone you can now move to the next item.
Craft bag / guild trader: have put these two together as essentially they use the same work around. You can still use L1 / R1 to move up and down the sections. After you click them flick to another tab and back and you are on the next section (or if you know how many L1 / R1 clicks needed on the right section). You can scroll up and down to find the item but again when you have gone up or down by however many clicks you think it is flick to another tab and back and you will be on the item you moved up or down to.
Alternatively if you know the name of the item you want to sell you can use the filters / search facility to get them to where they are top of the list.
As I say not ideal but workable, it takes a little longer than it used but is probably still quicker than with the lag we had been getting on these transactions since the last update