Honestly, I’d be surprised if static IPs fix it. Docker’s default network type (bridge network) is very good at assigning IPs to containers without clashing, even with container restarts and replacements: it’s been battle tested for years in production use. As others have said, standard DNS hostnames of containers should be sufficient. But I’ll certainly be interested to hear your results.
Aren’t we all? Aren’t Ext4 and ZFS considered mature because so many people have said “it works on my machine”?
I agree this person’s experience may contrast to your own, but I don’t think the fact that something has worked well for some people, and perhaps not for yourself, is a reason to discount it entirely.