I am not a keyboard warrior who got caught up in the nonsense, but I think some people were simply annoyed at adding syntactic sugar for very marginal benefit. “There should be one way to do things” mantra.

I have a long list of grievances with Python, but the walrus situation would never crack my top ten. Put effort into removing cruft from the standard library, make typing better, have the PSF take a stance on packaging. Anything else feels a better use of time.

Whatever, it won. I will never use it, but when I see it will have to scratch my head and lookup the syntax rules.

It was against many people's aesthetic sense. Including mine. But in theory it can be ignored completely, and in practice it is barely ever used (and indeed nobody forces you to add more uses).

You may be interested in https://learning-python.com/python-changes-2014-plus.html for a sense of what some old-timers' aesthetic sense is like. (I agree with many of these complaints and disagree with many others.)