I would agree.
The martingale strategy would be possible assuming that the person has unlimited resources in order to cover for the next bet. Again, we are talking here about the probability and the luck of losing- that is why the possibility of experiencing a losing streak may sound impossible but it is possible.
I personally tried this technique but I failed to recuperate after a 5-losing streak last year when I visited a physical casino. The amount exponentially increases as you lose but you tend to recover back your losings after one win.
A losing streak is very common in almost any game while gambling. I have faced losing streaks of 7, 11 and 16 and definitely it were some bad experiences.
I remember posting about one of these streaks on this forum and I found out it is very common to face these losing streaks.
Since gamblers like me have limited amount kept for gambling, the negative streak ends up the whole balance while doing a martingale.
I then realized it is better to stop gambling when we face upto 5 losing bets continuously and this method has saved me many times.