As much as you say that RSI doesn't hint towards the overall trend of the market, as someone who watches this very closely, I would say it does.

First off I would like to say that on a fundamental level, RSI as well as any other indicator for anyone new who's reading this only gives a possible direction that the market would go in not a concrete one. This means that regardless of how bullish/overbought a market is or bearish/oversold a market is, markets can still push to the upside as well as the downside respectively despite its indication towards the opposite conclusion as this video mentions. BUT even though the market doesn't do what we expect it to do on an intuitive sense, the RSI still does reflect market behavior i.e. if the market is overbought, the RSI drops a bit but then shoots back up to reflect the continued bullish activity which we predicted not to happen. The opposite is true for oversold markets. This concept continues on further even if the market meets our expected predictions for RSI despite the video saying that it doesn't. If one looks closely regardless of when you see the RSI drop or increase, it's always correlated with the general DIRECTION that the market is heading in. The key word here is direction and not MAGNITUDE. Whenever the RSI drops, that doesn't mean that the market will drop a substantial amount nor does it mean that whenever RSI increase, the market will increase a substantial amount. This is the point that I think is missing from your video. That despite predictions of the market increasing or decreasing dramatically based off of RSI predictions not being true for what we see in Bitcoin, we still DO see a correlated directionality no matter which time frame youre looking at.