That is the million dollar question.
Only the SPL clubs themselves know for sure. There will be a drop in revenue, that's a fact. How the clubs will/can cope with that and for how long is the big unknown.
Without any actual facts available we can only read bewteen the lines, and of course that is open to interpretation.
Here's my take.
It seems to me that some SPL clubs may genuienly struggle. I'm basing that on the Div1 debacle. These clubs were bweteen a rock and a hard place in the SPL vote. They faced a very real fan revolt if they voted yes so they ducked it and in cahoots with the SFA set about bullying the SFL with the Div1/SPL2 nonsense. That suggests to me that some SPL clubs have a very real fear over loss of revenue for more than one year. Otherwise, I think, this Div1 bollocks would never have been mooted in the first place and we would rightfully have been kicked to the 3rd no questions asked.
If we assume my take on it is reasonable then the standard of football will fall as the squeeze on these clubs grips and they have to cut their costs. Clubs who have no real fears over the revenue loss will have no reason to splash any cash to remain competative and can instead reduce their debts. The longer that continues the worse the standard of football becomes. Of course, at some point, that trend reverses as the clubs that reduced their debt become much healthier financially. The standard of football will rise again as they are able to splash the cash to push for honours. However, how many, if any, clubs will fail to survive that cycle?
Like I say, it's me reading between the lines and extrapolating and may be well wide of the mark.