I know that poker has more to do with skills than most other forms of gambling. But there are very short stints that luck comes to play. Even with all your pro skills in poker, you can still lose buy-ins in a row for varying factors. A poor bankroll management would just bring a highly rated poker pro to ground zero in instances like that.
Bankroll management is a must if you want to succeed as a poker player! Ability to know when to retreat and restrategize is very important in game of poker. If you want to succeed poker games, you must discipline yourself to stick to your bankroll management strategy.
Absolutely, bankroll management is mandatory if you want to survive long-term. You can be a skilled player but still go broke if you're playing stakes that are too high or not managing your money properly. Variance is real even good players have losing streaks. Without proper bankroll management, one bad run can wipe you out completely before you recover.
If you are playing poker and you don't have bankroll management, there is every chance that you would go broke at some point. Even the best poker players always have periods of constant losses. It is their bankroll management that keeps them afloat to keep playing in such times. It is bankroll management that allows poker players to survive variance.