Having IPv6 support is important, especially for IoT-Devices which might be
many, requiring individual IP-addresses. In particular direct access via
link-local addresses and having deterministic SLAAC-addresses can be quite
convenient. Also in IPv6-only networks or for connecting to IPv6-only
services, this is very useful.
For the Pico W, there is enough flash and RAM that enabling IPv6 by default
is the right choice.
Should IPv6 support in a network exist (i.e. there are Router
Advertisements), but not provide connectivity, connecting by domain name
should not be a problem as DNS will default to return the IPv4-address (if
that exists), unless reconfigured at runtime to prefer IPv6.
In any case a user can disable obtaining SLAAC-addresses with:
<nic>.ipconfig(autoconf6=False)
Signed-off-by: Felix Dörre <felix@dogcraft.de>