

You’re arguing that a dev shouldn’t be seen as supplying to Google just because their apps run on a Google system. I agree, that could be a valid argument, but I am not too sure if it would work in court.
Google is certainly following the spirit of the law. Maybe there is a tiny loophole here but imagine Google leaves that open. A few people install some shady app store full of malware and scams. Would a court find that Google had fulfilled all its legal obligations to protect its users?
Here’s a definition:
I don’t think it’s a stretch to say that such apps are components “placed on the market separately”. In fact, I think it’s exactly within the meaning. In any case, even if not, such loopholes are usually plugged by some of the vague, general obligations.
I don’t think ADB installation is a loophole. Once you poke around in the insides of a device, you’re generally on your own. I expect that devices are going to become more locked down before these regulations enter into force but only as far as absolutely necessary. Google doesn’t want to lock out the next generation of devs. Unless or until there is some fuss about people doing something bad and this is declared a loophole.