Like I said, it wasn't a fundamental analysis. I should have...

Like I said, it wasn't a fundamental analysis. I should have changed FPH to ASX as I used ASX A2m.
Even though this is not a fundamental analysis, even if you put numbers to it, the theory stays intact. ALL values in NZD below.

A2m market cap is 14.5bn. At a SP of 30NZD per share, the market cap would be $22bn (not 20bn as you suggested).

FPH market cap is near 17bn. Yes that is short of 22bn but wait... if we look at the NPAT last year, FPH did a measly 210m compared to 287m for A2m. A2 milk profit was 37% higher than FPH. 17bn x 1.37 = 23.2bn (even more than the $22bn market cap for ATM with a SP of $30). FPH FY is completely different to ATM so that needs to be accounted for but if we use the same PE ratio as FPH, $30 is possible.
FPH and A2m are similar in that they are both growth companies and have grown at a faster rate due to COVID 19. FPH has generally been growing in low teens and A2m is expected to grow in high teens for the mid term. Similar growth profiles although the terminal growth rate is probably higher for FPH as A2m will eventually drop to high single digits. The main difference is the sector and the fact that FPH is a well established company that has been operating for decades and delivered profit growth upon profit growth. If/when A2m gets up in the same league, it will be able to attract a higher PE.