As employees protected by the NLRA, they can formulate their demands and pass them on to their coaches and school administrators. This could be in the form of a letter or a request for a meeting, for instance. The schools cannot ignore the players' demands to be heard. The schools must respond in good faith or face a charge known in American labor law as an "unfair labor practice," a charge that can result in severe penalties and sanction from the NLRB. The universities, of course, are not obliged to agree to the players' demands, but they are required to listen to and reply to them.
What is the legal effect of the general counsel's opinion?
It is nothing more than the opinion of the current general counsel of the NLRB. Griffin was appointed to the job by President Barack Obama in 2013. His term ends in November. A new general counsel, appointed by President Donald Trump, could rewrite and reverse this opinion.
To me, the quotes above show the current situation as not being a whole lot different than it was. This is just an opinion of one guy, that can be reversed, and only allows players to make demands without penalty. It does not mean anything has to come out of it. Ultimately, someone would need to take on the NCAA in legal court battles.....and that could take years and a ton of $$.