God I hate this argument. Sure it is the future. But what you and other keep forgetting/not mentioning is the fact that USB 2 (type A) isn't going to suddenly disappear. There are just too many use cases where a bigger throughput from USB 3+ isn't needed.
So what do you do? Throw away all usb 2 peripherals? Buy multiple adapters? To think of all the usb sticks that would be basically useless without a dongle...
When apple decided that CD/DVD's are deprecated it was an ok decision because a) Most media can be put on an external dive b) you can buy an external CD/DVD reader. And i think you need an USB-A dongle WAY more often then an CD/DVD drive.
Apple should have just keep 1 usb 3.1 (Type A) port => 1 USB-A + 2 USB-C for the non touchbar MBP. If the macbook would then be a few mm taller, excellent. More room for the battery.
The best part about USB-C is Alt Mode support, it allows you to use any protocols you want as long as it is supported on both sides. In this case with Macs, the TB3-enabled USB-C ports mean you can use Thunderbolt 3 without changing the connector port and not lose other protocols like USB 3.1 Get 2 (10Gbps), Power Delivery, etc.
By saying future proof, what they meant is that any future products using USB 3.1 Gen 2 (10Gbps), Thunderbolt 3 (40Gbps) and/or power-delivery up to 80-100W will be supported on these MBPs.
And while I get most people can survive with 16GB today, limiting RAM isn't future proofing for people who plan on owning a Macbook Pro for five years. Over time, new revisions of operating systems and software tend to require more RAM, not less.