This morning while in Suzhou I managed to get a recording of some non-standard but surely common intonation. You can listen for yourself. It starts at around 4 seconds.

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It’s quite the descent. Putting that into Praat gives the following pitch curve.

This is still on the pinhole mic and the room was made of concrete so there wasn’t much that could be done about the heavy reverb.

People often say that in Wu, or at least in Shanghainese, tones don’t matter. I don’t think that’s really true or they wouldn’t have stuck around. Without really giving it much thought, the one idea I do have about it is this: We don’t really get into jargon in our native comfort dialects. When we do, we clear things up. I’d imagine if you’re pushing into some topic of greater complexity requiring more words that are homophonous with other common ones, it would be more important to hit tones. Get in any taxi in Shanghai and say Nānjìng Xǐ Lú and I can guarantee you you’ll still make it to 南京西路. Try that in a real conversation and you might not be so lucky.