I have not seen a single person confirming that their XS Max is performing equally to an 8, 7 or 6 in low signal areas.
So speaking of not paying attention...
My wife has a QC 8 on T-Mobile, and I have an Xs on the same carrier and account. There have been many instances where her phone was showing 4G or E while I was still holding on to 1 bar of LTE. We recently traveled from Indianapolis to Destin, and ran across many backwoods areas in Alabama with little or no coverage, and in every single scenario we noticed my phone had service wrote hers did, and would hold service longer than hers.
So what exactly are you looking for here? Do you need video of the phones side by side traveling every inch of Florida with Tim Cook riding shotgun while singing Elvis? I’ve posted results from good signal areas where people have complained that their Xs is slower, and I’ve posted results from bad signal areas where people claim their Xs can’t hold on to anything. Do you need one with 2 bars of service while I’m standing on my head in a vacuum chamber to see if it has any ill effect on the antenna?