Hamburg is very different to Lederhosen Bonkers Beer Hall Land which is where all this stuff is cooking up at the moment.
Yes and no. The lowest vaccination rates are not in Bavaria (or over the border in Austria which is culturally similar) but actually in the Eastern German states. The reasons for hesitancy there are also common to former Eastern block countries. The eastern states have also been much more hesitant with masking and vaccine passports.
Hope you're right. Was hoping to go to Hamburg in December. Sick of it now. Absolutely sick of it.
I reckon you will be okay as long as you are willing to comply with the state rules (of Hamburg) on demonstrating vaccination status and mask wearing etc. You can read all the stuff in English on the Hamburg state website. Recommend importing your NHS vaccine certificate onto the German Corona-Warn App (all available in English) and then it generates an EU certificate which your hotel and restaurants/bars/cafes/museums can scan. They may be able to scan the NHS one now, but I would import it to be safe.