From my experience managing sites, site owners need to upgrade to take advantage of new technology - which includes updating protection from hackers and their ilk. When managing multiple sites, having a common unified platform greatly simplifies the care and upkeep, as well has providing for future growth. As it has been said before, forums change and evolve. Anyone remember the original BBS's on Compuserve?
These sites exist to make the owners money, it's how this country works - I have no problem with that. I'm just making an observation - as with consumers of any product, you need to decide for yourself if you continue to use it, try to show the producer the value of not making the change, move on, or build it yourself (kinda SS-like, no?)