I just checked their site and it states that the page was Last Updated:12/31/2019 which would qualify it as "brand new", but in a strictly manner it doesn't necessarily means that this is also the date the firmware was released.
What let me doubt is this page which explains the benefits of beamforming+. That document was Last Updated:11/28/2016 but already refers to their "newest" firmware 22.214.171.124.
In conclusion: Which reality is really real? ;- )
PS: Just checked the referred R6300 is now on 126.96.36.199, so 188.8.131.52 seems not really the latest and the greatest.....really a smart move from netgear not to publish a release date next to the firmware images.
PPS: If someone has installed 184.108.40.206 on a R7800....what is stated inside the firmware?