I've seen it said that folks can learn all that there is to Dungeons & Dragons by watching live shows, videos or livestreams.
Not even close.
Watching Critical Role, or Acquisitions Unlimited, may get you on the board but it won't teach you everything because the game changes at every table. My table is significantly different from the D&D assumed by those two aforementioned campaigns, or the MissClicks campaign, etc. as it has far fewer player-accessible options for making and developing their characters while using Early Modern instead of Ancient or Medieval Europe as its inspiration. (Yes, that means guns and gunpowder.)
Is your table Open or Closed? What races and classes are allowed? What weapons, armor, spells, etc. are allowed? Is this a sandbox game or a themepark? Alignment used? If so, what is allowed? Where does the campaign take place? When? How are the acquisition of new capabilities handled? How is the economy handled? What other elements not in the rules must I know, and what rules are either not as-written or not used at all?
That's just dealing with the rules and setting. Now comes the real difficulty: the full experience of a tabletop RPG cannot be had by just watching. Just as the only game that exists is the one at your table, the only engagement that exists is by those at that table playing it. Watching or listening does not cut it. Much like fucking, you can't grok it until you do it and once you break through you won't ever ungrok it.
That's because the power of the medium doesn't rely on external audio-visual stimulus. It relies upon your imagination of being your character, living his life in that moment. The entire "What do you do?" feedback loop is the foundation of the medium for that reason; you are compelled to put yourself in that position, acting only on what your character perceives of the situation and has at his disposal to address the problem before you, and a competent Game Master will push you for time as your character would so as to keep you properly immersed in that moment and thus have that virtual life-experience that you--the player--can learn from. It's different when it's your (virtual) ass, and spectating can't deliver that.
So, instead of saying that watching is equal to playing for getting curious normies to try out TRPGs, be smarter than that and read this far more useful article on Open Tables as a normie-friendly way to get them playing instead.