Can hold back? How? Or are you just guessing?

The binary is typically compiled for ARM making it very hard to use it somewhere else without fiddling a lot. By using a simple license key system (if the application actually is worth protecting at all), it's not impossible to circumvent it but often not worth it if the application has a price that's intended for online purchase. People in general actually tend to pay for online content if they think the price is ok.

The main incentive for companies to produce and release software is to make money. Imposing DRM is not an incentive for companies to produce software. To actually get a DRM solution that's both flexible enough to work transparently and be future proof is lots of work which costs lots of money.

If this is done to protect something that's sold for $7 a piece, the math is simple: it's a waste of time and effort and it will only hurt people who actually pay for the official version if the DRM fails to function in the future. This has been showed again and again when those who have paid for a game are forced to use cracked versions just to use the product when the DRM solution fails.

DRM is corporate smack talk that tries to solve the wrong problem.