There's definitely a correlation. I just had a look at a sample of middle forwards from round 5 (just to pick a round) of 2016 and compared them with the fifth round of 2021 and found that six middle forwards in round five this year threw 10+ passes (Harris, Trbojevic, Peachey, Jackson, Radley and Brown) while in 2016 the only one was Greg Bird. The game has definitely evolved, and plenty of teams use a number 13 'middle half' now. This is distinct from the 7 (or 6) who plays between split fullback and 'five-eighth' on either side, though as I said, it looks to be connected.