While this developer may be overreacting (he probably doesn't need a DPO), i understand why it might just be easier to block it , at least until there are precedents about how to comply and more info on how the regulation will be enforced.
GDPR can be scary for developers, because nobody actually knows how a website or app is supposed to work (I have yet to see a single example), and it requires a series of steps that are not trivial on the administrative side. The Right to be forgotten is the easy part. Having to document everything you do and introduce data-dumping mechanisms that are both anonymous and secure is administrative burden. Having to do that for every little project that you release, even if it has 10 users, is a bit too much. Many developers cast a wide net, releasing products often, and this is practically unnecessary work unless you have a significant amount of users.
Introducing opt-in forms everywhere is also not great. It didn't work for Windows Vista so why do we expect this to work on the web? Opt-ins for things like cookies should be implemented on the browser. What's the point of warning a person before sharing their email? What's the point of warning them even you 'll install a cookie? IP addresses and cookies etc are integral parts of the HTTP protocol and the browser so why not introduce anti-tracking regulation that targets browser vendors and telcos instead of introducing regulation that targets every developer on the planet? It doesn't seem like an optimal plan imho. The example of the cookie law (for which it's hard to argue that it has not utterly failed) should act as a bad precedent, not a good one.
It's easy for US developers to be positive of GDPR because they can avoid the overreaching parts, but for us in the EU its something we have to abide by 100% of the time. I 'd like to hear what other people think about those, because otherwise i hear a lot of emotional praise for GDPR which is blind to how problematic it is at day 0.