What a load of shit. Evans has been top 17 at the Roosters since 2015. Mannah has been top 17 since he was 21 years old. Matagi is in his second year of being a top 17 player, as are Vave and Terepo.
Obviously these guys wouldn't all be top 17 at every club, but I reckon Mannah, Brown and Evans would. The others would be top 17 at most clubs.
The point is you don't need one player to be your 'number one prop'. You just need a certain amount of combined attacking output from your middle forwards as well as effective defence. Defence is the responsibility of everyone - you can't ask the opposition to just run at your best defenders - and there is no reason to require the bulk of your attacking output from just one or two middle forwards.
You're missing the point, there's probably 6 middle forwards in a Top 17 at every NRL club every weekend. Some teams run with 5 1/2...
Anyway, all of our middle forwards outside of Brown and Scott would be considered number 5 or 6 at most other clubs. In fact the two new ones, Vave and Matagi, were considered that and even lower at their previous clubs.
Players number 3 to 6 are the players you describe above, the ones who are there to provide a certain amount of combined attacking output (hitup metres) as well as effective defence. It's middle forward number 1 and 2, the ones who bring to the table above just hitup metres and numbers of tackles, the players who might only give that 1 percent differences in certain areas, that will make the difference in any given much come finals time.
The last few Premiers have had this player.
2016 - Sharks - Fifita and Gallen
2015 - Cowboys - Scott, Taumolo and Tamou
2014 - Souths - Burgess x 2
2013 - Roosters - JWH - but then they had Cordner and SBW on an edge, so only needed one great middle forward to go with their 3 to 6's