"In England you see young guys, maybe 26 years of age, who might've played 100 first-class games. They have marked 'centre' that many times and have so many failures and successes that it helps them learn and mature quicker."
Williamson's passion for the issue is obvious. He was prepared to speak to the Herald on Sunday at 2am on Friday, in the aftermath of his Barbados Tridents' victory over the St Lucia Stars in the Caribbean Premier League.
The conversation came after the West Indies and Bangladesh achieved upset test victories over England and Australia respectively in the past week. Those efforts prompted Williamson's New Zealand teammate BJ Watling to tweet: "Couple of enthralling test matches this week. How good? #testisbest".
As test specialists, the likes of Watling, Neil Wagner, Jeet Raval and Henry Nicholls might be restricted to four chances to showcase their international skills this home season - two against the West Indies in December and two against England in March-April.
Unless further bilateral fixtures can be arranged, those will be New Zealand's only tests for the 18 months between the rained out draw against South Africa at Hamilton in March and a proposed October 2018 tour to play Pakistan in the UAE.
The last time New Zealand played less than five tests in the southern hemisphere summer was 2006-07 before the World Cup. It has become the norm to play more than four across the season, albeit with the first occurrence only coming in 1994-95.
Williamson hopes efforts are devoted to persevering with tests.
"I know I'll be part of a few discussions in the next wee while, but I'm a big advocate of the test game, so I'm open to new ways to keep it attractive and at the forefront of international cricket.
"Many of those I talk to still believe it is the pinnacle of the sport because it challenges you in so many ways; and that mindset underlines the importance of the domestic first-class game.
"Introducing pink ball day-night tests might end up as a good initiative, but we had some fantastic test matches in our most recent summer - and for two to three summers before that - and got some reasonable crowds as well."
Williamson says the test format needs "a push" and that could be as simple as the introduction of a global championship from 2019, as proposed by the International Cricket Council.
"I know test cricket is under pressure in places, but it's thriving in some countries.
"This season there are only four tests [in New Zealand]. Players would probably like to see more long term.
"The test championship's really important because it makes things relevant, so the audience knows what any game means and where a team stands. It will allow fans to connect more, as opposed to a rankings system that few people really understand."
Williamson likens a cricket test to a golf major with the ebb and flow leading to a crescendo over four rounds.
"Part of going into the new negotiation is looking at the structure we have. I know NZC will talk to plenty of people involved.
"A number of players within those conversations share a similar view in the importance of the longer format.
"The shorter format helps people gain an understanding of the game. I'd love to think that then brings an interest in tests."