Can you explain why downward bit support (in lack of better term) can be a bad thing, or point me in a direction that might help me understand this better? I do agree and understand that legacy stuff is very often unwanted. It's not like a have floppy or PATA support on my computers.
Strictly from development standpoint - I believe that a true 64 bit application should remain crisp and clean - meaning it should only support it's native plugins and should not have any conduits (bridges) that allow "old 32 bit tech" to run inside the host environment.
My main concern with this is certainly not to leave people hanging that want to use there old plugins - but more for those of us who have made the investment and the decision to move forward. Allowing 32 plugs to run in a 64 app can breed all sorts of nonsense since the designers of said 32bit plugs cannot be counted upon to have built their plugs to run properly in such an environment.
Conversely - adding a "bridge" into the mix forces devs like PG to constantly run around tweaking his conduit every time a bum plugin is encountered. From a paying customer angle - I would rather see PG working to give us the best possible Wavelab he can rather than worrying about why some 2002 32 bit plugin is crashing his 2014 WL release.
Cubase and Nuendo are "bridged" and gave me fits for a long while - until I dropped Nuendo completely and moved to pure 64 bit with Studio One V2)
From a personal standpoint - if one is moving to 64 bit - one needs to truly move. If your vendor cannot get off their butt and create a 64 bit version of a standard go-to plug - then I would think seriously about staying with that vendor.
Given it's 2014 - going on 2015 and 64 bit is now the norm - I cannot see any reason to use any 32 bit plugs..but if you really need to - Wavelab comes in both flavors and can accommodate any plugs whether 32 or 64 bit.