Every time I start ddev on my Mac, I get a message: Internet connection not detected. There does not appear to be an operational issue, and I can reach the internet from the web container.
I could not find any reference to this message in the ddev docs.
First, ddev v1.16+ is much less annoying about this, so I imagine you should upgrade if you haven't already.
Second, the biggest cause to date has been problems with Fritzbox routers and dnsmasq set to disallow DNS rebinding, please see https://github.com/drud/ddev/issues/2409
ddev uses the ability to look up *.ddev.site as a proxy for whether it can connect to the internet (or whether it has to add an entry to the hosts file). So if it can't look that up or if it's too slow, it complains.
As mentioned in the comment, you can edit and increase the internet_detection_timeout_ms in ~/.ddev/global_config.yaml
