I think some of the night photos are out of focus, especially Pixel's. And the translation obviously needs some work.
As for the night shot that's in focus, IMO Pixel's stands out, indisputably. Pixel's is, as it has been for a few years, the only one that has "structure". At a ~900P size the Samsung might match the Pixel, making it a matter of preference, but at 100% the Samsung lacks structure, just as the Xiaomi and the Huawei. Additionally, the Huawei loses color data as the RYYB tends to in certain circumstances, and the Xiaomi has some huge blots in the distance resembling artificial bokeh. I hope that's not because artificial bokeh is somehow baked into Xiaomi's night mode.
When the Pixel messed up the first night mode shot I believe it was probably an error in automatic settings and/or a transient focusing issue.
IMO the Pixel is as reliable as your manual settings make it (auto is an issue) and how steady your hands are, but other models are often unable to make use of additional exposures allowed by a steady hand.