"Mason [Emerson] went very close with some strong performances and put his best foot forward. But he was up against two guys who are already proven at the next level," Philpott said in reference to Chiefs player Shaun Stevenson and Blues player Jordan Trainor.
Kean was hindered by an injury across the Tasman and Rakete-Stones will be eligible for the Baby Blacks next year.
"While we were impressed with Pouri, his year is next year. He needs to put more meat on his frame ... he is 108kg and there will be props at the tournament around the 120kg mark," Philpott explained.
Lowe was considered unlucky not to make last year's world championship-winning Baby Blacks team.
"Last year was preparation for this year. I've trained hard-out and all that training has paid off," Lowe said.
While he alternated between the left and right wings during the three games, he won't mind either role or a midfield berth in Manchester.
"I'm just happy to be a part of it. I asked the coaches what they wanted me to do and I tried my best to make them happy. I just managed to do enough," Lowe said. "The coaches told me to get involved, be confident and have a go. In the second game, I didn't get much ball but I worked hard defensively. In the third game, play came my way and I went well," he said in reference to a game in which he scored a length-of-the-field intercept try.
Six of the Baby Blacks squad have Super Rugby experience and Lowe said it will be good to have them on board in a squad which has a different look to the one taken to Aussie.
"It's important we start well and don't take any team lightly," Lowe added.
The Baby Blacks will open their Pool A campaign on June 7 against tier-two competition winners Georgia.
They will take on Ireland on June 11 and Six Nations under-20 champions Wales on June 15.
Before flying to the northern hemisphere, the Baby Blacks will play the Chiefs development side in Mount Maunganui on May 30.
In addition to focusing on his duties with this national team, Philpott is waiting to hear whether or not he has been shortlisted for interviews for the head coaching roles with both the Crusaders and Highlanders.
U20s Squad:
The full New Zealand under-20 rugby squad for the June 7-25 World Championship in Manchester:
Outside backs: Jordan Trainor (Waikato/Blues), Shaun Stevenson (Waikato/Chiefs), Caleb Makene (Canterbury).
Midfield/wings: Malo Tuitama (Wellington), Jonah Lowe (Hawke's Bay). Midfield: Patelesio Tomkinson (Otago/Highlanders), Jordie Barrett (Canterbury), Orbyn Leger (Counties-Manukau).
First five-eighths: TJ Va'a (Wellington/Hurricanes), Stephen Perofeta (Taranaki).
Halfbacks: Sam Nock (Northland/Blues), Jonathan Taumateine (Counties-Manukau).
Loosies: Hapakuki Moala-Liava'a (North Harbour), Marino Mikaele-Tu'u (Hawke's Bay), Dalton Papali'i (Auckland), Luke Jacobson (Waikato), Mitchell Jacobson (Waikato).
Lock/loosies: Fin Hoeata (Taranaki), Isaia Walker-Leawere (Wellington).
Locks: Quinten Strange (Tasman), Hamish Dalzell (Canterbury).
Hookers: Asafo Aumua (Wellington), Leni Apisai (captain, Wellington/Hurricanes).
Props: Sosefo Kautai (Waikato), Alex Fidow (Wellington), Sean Paranihi (Canterbury), Shaun Stodart (Otago), Ayden Johnstone (Waikato).
