There are many ways to do it if we really want Bitcoin, we don't always look at the price and I agree as you said if we can use the DCA method to collect Bitcoin slowly with the money we have, it will be more effective.
However, if someone sees the current price of Bitcoin, of course it is expensive and not many people can afford it, it's all a matter of mindset and anything we can get if we really want it.
When the price is considered too expensive by every Bitcoin buyer at this time, of course they will all also find their own way to get Bitcoin and one of them is the way you said because it is always based on the level of ability that each person has when they want to buy it. But for those whose income is not too much and can only be enough for their daily lives, maybe another option they can take is to seek profit through airdrop programs or altcoins so that the profit can also be used to buy Bitcoin even though something like that may not always be there to be obtained.