Don't want to get too far into that topic but I think it's more to the point that City and the rest of the big 6 overtook like likes of Celtic and Rangers ages ago. Domestically in their country there is Celtic and Rangers, so it's fair to say they are have been a bigger deal in their own country than City have for 9/10ths but when was the last time Scottish football was as relevant globally as English football(has it ever been)? The English game wasn't always global either and the USA if we're focussing on that, has not historically taken to 'soccer' in the numbers it has today. Spurs are bigger than Celtic today IMO.
They cling onto absurd metrics such as the number of supporters clubs or the number of fanatics who have opened bars abroad(Scottish expats supporting Celtic?.. Wow). They can open as many supporters clubs as they like(we have more than Liverpool and United) and 'themed' bars too(bit tacky IMO) it doesn't really mean much though.
Take a look at the TV deals which is as good an indicator of the global interest as any. Scottish football is below Austrian, South African and Indian football on their deals. More in line with A-League(Australia). Though it also says, per game value Scottish Premiership ranks 10th. Probably something to do with the space Sky has for it, since they only show 60.
Anyway,
Andy Townsend talks shite. City are definitely far bigger than Celtic globally today. So he can stop taking cheap shots now. I seem to remember he said City are bigger than Arsenal(I'm not sure we are globally yet) and Chelsea(yes) but not Celtic. Sutton once claimed Celtic reserves are bigger than Leicester as a club too. Is it a cultish-hipster thing people do to appear trendy? They're not even Scottish, I don't get it.