Maybe the question here is not so much "should board meetings be recorded" but rather what effect does recording have on board effectiveness?

Leaving aside the legal considerations, which are important, one might argue that if  full and frank discussions cannot take place, then decisions might be different to those had that information been presented. I suspect that a board member might be reluctant to discuss in a full and frank manner if he/she believes that those words may lead to either legal, personal of industrial implications. This may impact outcomes. As official minutes are generally santised, such problems occur much less frequently in a purely written form. Therefore I have no doubt that in many instances, recordings may hinder board effectiveness.

The other context is when a board takes poor minutes and has experienced many disputations about what was actually said and agreed at a meeting. Recordings may certainly help corporate memory but may hinder personal contribution for reasons mentioned.

I feel however, that verbal presentations made to the board by non-board executives might be recorded because the entirety of the presentation is the "evidence" upon which the board relies, deliberates on and uses to resolves matters. Opinions, comments and other statements made by executives in support of a view are important to the resolution of the issue in hand. The problem with this however, is that honestly in such statements may also be stifled as with board members. The fear of "retribution" within the organisation for honest (but not necessarily accurate) statements is a real influence on subjective decision-making.