Does it mean its just best to trade on daily or weekly chart than doing it in hourly or 4 hour time frame?
the higher the time frame, the more reliable the signals. that's the rule of thumb.
i still look at the 1h-4h charts, but the higher time frames dominate. for instance, if the daily is deeply oversold indicating a strong downtrend, i'm not gonna trust RSI bottom signals on the 1h chart.
I see the link going mainly to Forex trading lessons, I'm not sure how to look at it when prices in Major currencies are stable than trading on BTC/USDT which prices can drop hundreds of USD in hours.
RSI is just an oscillator. it works relative to the volatility in the lookback period
regardless of which asset you're charting. it works equally well on any asset.
forex vs crypto doesn't matter. the fundamentals may be very different, but the TA is the same.