The reality is that transfer fees will always be relative to the amount of money in the game in general, and specifically how much cash flow a club has at its disposal.
It's better to judge fee's as a % of a club's profits, rather than YearOnYear and vs each other, to get a proper indication of how much risk a club is taking.
The new TV deals were always going to increase transfer fees. TV deal will continue to increase over next few years as there is still plenty of viewer growth to be had from countries like US, India, and China, which will increase a broadcasters ad revenues.
Taking the above into account, and seeing this year's fee's pan out, Pogba's deal was in line with the market trends, maybe even slightly lower, but we were slightly ahead of the trend.