DAC started out as a community of practice

I think more options need to be developed for actual tool users and tool integrators inside of customer firms to present and interact. DAC has a position relative to

vendor user groups, (e.g. SNUG, MUSIC, CDN Live)
purely technical conferences,
other trade shows, (e.g. DATE)
other workshops (like the Electronic Design Process Workshop in Monterey),
trade shows for adjacent areas (Embedded Systems Conference, FPGA Summit)

It has historically been focused on multi-vendor (including in-house tools) design flows, in the last decade or so it's narrowed more to ASIC/SOC and had less to do with FPGA and PCB for example. O''Reilly with the Maker Faires is doing a fair amount with FPGA based design that seems to attract a much younger demographic that DAC, which gets a little greyer every year. I guess one possible "death spiral" is academics and vendors talking to themselves while users take a week off.