I don't think the message was that candlesticks themselves are a scam, rather that they are often used by persons to sell products based on candlestick "magic". As with all things, it is down to the individual trader to understand what a candle is showing in the context of the timeframe that one is using and the other price "clues" that the market is offering. "clues is an excellent term for that!
The problem, as always, is not in the indicator or PA line or pattern or candlestick formation, it is in the trader not doing sufficient homework to understand what they are suggesting. It is no good just saying "aah look there is a Doji, therefore the market is going to do this.........".
A 5m candle formation is invisible on a 1H chart, and a candlestick on a 1H chart is invisible on a Daily chart. If a candle is to be of value then it should be viewed either purely within the constraints and limitations of the TF being used, or, preferably, in the overall context of the situation in a higher TF.
There is nothing magical about candlesticks. The price flows in a constant stream. Candlesticks just break that up into a series of arbitrary time-based units each with its own OHLC. If we like, we could say that candlesticks are like looking at price as a series of still shots rather than as a movie. But if you flick through those still shots as a series then you can, and do, still see a pattern that is significant.