I do it, everyone and their grandma does it. Farm SW, let a mid-level alt open the bags, profit (or at least be able to feasibly craft ascended mats). But is this really working as intended?
Surely one of the reasons mid-level mats were included in ascended crafting was to give people a reason to go back play mid-level maps, and keep those maps from becoming dead content. But with the way drops work for level 80 characters, they mostly still get T5/T6 even on those maps, thus SW farming + alts as a more reliable approach, but one which entirely circumvents the purpose of making those mats valuable in the first place.
Now, there is a similar bag system introduced in PoF with unidentified gear, but that always gives level 80 drops, suggesting that ArenaNet sees the phenomenon of bag-opener-alts as a mistake to be corrected. So, the questions:
1) Have you considered reworking drops on core Tyria maps to make mid-level mats more accessible to level 80s who actually play in the appropriate zones, by using the scaled character level rather than the actual character level? While I can respect the design theory behind the current system, it was implemented prior to the existence of ascended crafting when T5/T6 were the be-all and end-all of endgame mats, which is no longer the case.
2) Once there is a way for lv80s to get low tier mats by playing on low-level mats, is there a chance you might revisit champ and gear bags in the loot tables and replace them with versions that open at the level of the character for which they dropped, rather than the opener?
I understand that either is something of a massive undertaking, but if getting people into sub-80 maps is still a desirable goal, then it seems necessary, and it might tone down on the farming at the margins and get people back to exploring and doing new things from time to time.