Having worked with a major eCom platform as well, this is exactly the standard case. Both shipping and tax are complex problems which do not have a simple solut

Having worked with a major eCom platform as well, this is exactly the standard case. Both shipping and tax are complex problems which do not have a simple solution for scraping by a search engine. Shipping is often highly dependent on the location of the buyer and often involves full estimate calls from each carriers APIs (USPS, FedEx, UPS). The only major data point I would focus on is whether the shipping is free or flat rate. Tax is even more complicated. Merchants often outsource tax calculations to a third-party service such as Avalara, which calculates unbelievably complex taxing schemes even down to the zip code, as tax laws are becoming increasingly more complex. Because of these reasons taxes and shipping are not widely useful data points for search engines. That may change in the future, however. I could imagine it becoming another SEO topic to be accounted for, similar to meta tags on product pages.