likely to deter the majority of future owners from wanting to get involved -
Chelsea fans own their ground, entirely. Have Chelsea struggled to attract investment? Don't go down the route of them being bigger, a Premier League club, because levels of investment are also relative.
While having real estate may well attract some investors, football clubs are hot property in several markets right now. You do not need to believe me, but I know for a fact people have and still do show an interest in the club despite the current ground ownership situation. The biggest challenge to outside investment is the clubs ownership situation.
Anyway, seeing this as a one and done vote is silly. There are many of those who voted against it that could be persuaded even with the current ownership. They need the right safeguards put in place and for the club to put some real time and effort into the plans beyond some concept art and a business case that looked like it had less than a day spent on it.