1) copyleft versus non-copyleft
2) which copyleft license to choose
3) the strategy of the dgraph
Regarding 1), non-copyleft leads to higher short-term adoption, but copyleft is often the better choice long-term. Moreover, history has shown that if you switch from a non-copyleft to a copyleft license, people will feel tricked. So the "early stage" argument doesn't hold. If you want to use copyleft long-term, better be honest and do so upfront.
Regarding 2), whenever you ask a lawyer in that field, they usually tell you that AGPLv3 is almost always what you want, preferable to GPLv3 and most other alternatives. So the "draconic open source license" argument doesn't hold. AGPLv3 just closes large holes which GPLv3 left open, to ensure that people actually stick to the copyleft principle. So if you want copyleft, choose AGPLv3 unless you have a very compelling reason not to.
Regarding 3), the dgraph people seem to see it a similar way: