Yea, 16GB is definitely the better bet for longevity. 8GB is still fine for the everyday user today (and by that, I mean the majority of users who are browsing the web, writing, running basic productivity things, using their computers for meetings and school, etc). But five years down the line, it's gonna be tight.
Most of the computers that are still in use 7-10 years after their release were able to have their lifespans extended by virtue of having upgradable RAM. With that now being a thing of the past, we aren't going to see quite the same level of longevity that we've seen before.
I recently looked at the original 2013-era retina MacBook Pros (the first ones to ever be released), and they also came with 8GB of RAM on the base config AND had the same $200 upgrade price for 16GB. That upgrade price hasn't changed, and it's been 10 years.