I wouldn't worry about it OP. Things change, no decade is just like the last. End of the 90's were Man U / Arsenal getting the big bucks of the newly formed EPL, mid-to-end of 00's introduction of the big spenders. The end of the 10's is going to be just as different IMO. Just look at the legacies of history. It was very rare for any great ruler to last more than a few decades, in the same way it will be rare for these sheikhs and oligarch's to sustain the clubs they've bought for the same amount of time.
... and remember being a fan isn't just about the good times. We rarely pay out much of a dividend so the vast majority of this money is remaining with the club which bodes well if any adjustment happens to the football market. Sure we've written off a few seasons and I expect a few more will be written off in terms of trophies but we're always in with a shout and that's something we have over most of the fans in the EPL.