so yeah you can use martingale as long as you are capacitated in having funds to sustain that.
That particular gambler who asked such a question is a complete amateur since no gambling site forbids their players from using strategies since they are aware of the fact that none of them can defeat their edge in the long-term.
Also, I never advise using Martingale if your goal is to seriously earn money in any gambling site.
This strategy is not new anymore and we know its effect in your gambling activities, some are able to make profit out of this strategy but most of the gambler believes that Martingale is not a good strategy and it didn’t work well for them.
There had been lots of discussion about martingale methods and its variation in this forum and we already established that this kind of method is very devastating especially when a player experience series of losses. It can easily deplete thousands of dollars and the player will have trouble in recovering once they hit the max bet in a losing streak.
This strategy is too risky and if you think to beat the house, you should not rely on this strategy.
The only strategy that can beat the house is to quit while still winning profits. This way the house can't have the chance to recover the winnings of the player. And best if the player withdraws it and use it elsewhere worthy.