For LND operators weighing this, LND's own zero-conf doc sets out today's constraints:

• Both sides need protocol.option-scid-alias and protocol.zero-conf set, or zero-conf channels won't work.
• When LND opens a zero-conf channel, it must use the anchors channel type. That's the limit you're describing.
• As the receiving side, LND can already accept a zero-conf channel from a non-LND funder such as LDK, but only through a ChannelAcceptor, and the scid-alias feature must be negotiated. Without a ChannelAcceptor, LND fails every incoming open request.

Source: https://github.com/lightningnetwork/lnd/blob/master/docs/zero_conf_channels.md