Honestly am just amazed at how many people including the OP is saying that bankroll management is not a strategy. In the real context, what is even meant by ''a strategy''? lay down plans for future achievements, isn't it?. Now when we are talking about bankroll management which what will sustain our gambling budget in the long term. Honestly, bankroll management is a strategy that is set to manage our money that is set aside for gambling, if it's not a strategy then we can just use up our bankroll within ''a blink of an eye''. So, for me, bankroll management is a strategy.
For some people, it is a strategy just to a certain level while for some other persons it is not a strategy at all since it doesn't shows that they can win their bets through it, it is just something that tells them how much to stake with at a time and the amount not to use. They don't realize that without it, they can quickly zero their account because there won't be that need to remain disciplined in staking with just a specific amount for a long time.