It’s not just the RAM, but also the SSD. 16/512 or better 1 TB is the ideal starting point, more is always better.
But where is the complaint? From the MBA to the Max there are various sizes and power levels, ports and looks to choose from. Could RAM and especially SSD be less expensive? Yes, absolutely, I would be happier if 8TB would come at the price of 4TB and be closer to the market value. Even with added cost for building the CTO machines, the prices are aggressively high. But apart from that, and keeping in mind where the brand positions itself, I still see nothing really comparing to these machines, whether you get an entry level MBA or a fully stacked MBP.