Today I went to an Apple Store for an appointment at the Genius Bar for this #yellowgate problem that I experienced on my brand new iPhone 11 Pro Max 256gb Spacegrey. Before the appointment, I looked at 6 other iPhone 11 Pro Max's by turning TT and everything like that off. I saw that all the display models had perfect screens in terms of brightness and color (so not yellow). During my appointment I pointed out this phenomena and the technician told me that they ran on a different OS compared to the ones normal consumers use. The technician then proceeded to look at my iPhone by comparing it to 3 other iPhone 11 Pro Max's (with everything turned off) of his fellow colleagues. My iPhone was the most yellow one but had a maximum brightness that was significantly(!) higher. The 3 other iPhones were clearly less yellow but we saw that the less yellow the screen was, the less bright the screen was. Even they were very surprised about all of this and questioned the quality of their own screens. So, I don't really think it is worth playing the lottery. I would only do it if you have a very dull looking screen.
Contrary to popular perception, yellow can actually be perceived as brighter for the same measured brightness.