The point is that the business is very different - an almost-ready board game has spent just 5-10% of its total budget because all the big money is needed for manufacturing the production run; so an almost-ready board game can need crowdfunding to make it.

However, an almost ready computer game has almost all of the effort (and money) already invested. If it's 90% ready, then it needs some 10% extra money and some beta testing, so it can go on an "early access" sale but does not need crowdfunding to get released.

And if it is at a stage where it still needs 90% of the total budget and wants to gather it from crowdfunding, then you can't apply the same ideas as from a boardgame, because a computer game can't be ready for play until much (or most) of the work and money is already spent, like you can with boardgames.