That step took effect starting from the 1983/84 season, IIRC, and City were every bit as complicit in conniving for this measure to be brought in as any other club that. The term 'Big Five' only really took hold in the mid-1980s when the top clubs, having achieved their aim of the home club keeping all gate revenue, moved on and sought a much more inequitable distribution of TV cash.
As was discussed on here recently, in the late seventies and very early eighties, there was no real talk of a 'Big Five', but sometimes people did speak of a six, based on the potential to draw a 40,000 home average attendance. We were the sixth, and indeed over the 8-year period between 1975 and our relegation in 1983 we had comfortably the third-best gates in the league. Until Swales blew it, we were regarded as an indisputably big club and had the influence that brought. Swales used it to campaign very actively for the abolition of sharing gate receipts.
Swales was also very enthusiastic about the formation of the PL. But he can't be regarded as a prime mover in that development, at least, as by then he'd overseen a comprehensive diminution of our status and he was really clinging to the coat-tails of
I certainly complained about it. We had great facilities and were drawing 46,000 fans per match, and, even with our ups and downs in the 1980s and 1990s, had a much more illustrious history that Pompey, playing in front of 20K a week in an absolute shithole and with barely a season in the top flight in living memory before the 2000s. And that PL run was gained based on cash injected by a bloke in his twenties with no ostensible track record of his own in business but a father who was subject to an international arrest warrant and avoided arrest because he'd managed somehow to procure himself an Angolan diplomatic passport. It stank, but there wasn't a peep from the press.