Yes, I don't think you are the only one this happens to
It's a good question and I suspect everyone will have a different view about those years but by common consensus, whilst the start of his ownership contained some positives and some good 'spin', by the end the club was at its lowest ever ebb (and yes I am including the protest year as that brought the fans together and there was a common purpose that you knew would stand the club well in the future). It was a bleak period in our history - to contrast with the current era, I remember a midweek game against Fife that we lost in OT where the attendance was somewhere in the 600s.
Prior to his ownership, the club had been kept competitive by excellent recruitment from (notably) Gerard Adams and Neil Francis and before this era there was a sense of us punching above our weight and whilst we didn't win much, we regularly humbled other teams and there was always a sense of a united club, waiting for the new arena and beating a few teams up whilst we did so. It was a decent time to be a Devils fan and 'G' and 'Franny' typified this, they understood the club and the fans.
Then came the new owner. Others can fill you in on exact details but the one thing that happened is that the fanbase was divided by a series of decisions that seemed, at best, not in line with the club's ethos. Adams and Francis were replaced by the late Brent Pope who had many qualities but coaching hockey teams and general man management were not two of them and the communication around the club collapsed. Worst of all the DNA of the club, winning and putting players first to give them the opportunity to do their best, were eroded. The club became a laughing stock and we had huge turnover of players, the majority of whom should have been nowhere near a Devils shirt. Much of the blame went to Pope, again, others closer to the club at the time will say if that is fair but the owner appointed him so..... to blame one man is disingenuous.
I don't know the reason for this and wouldn't heap all blame on the owner (I haven't got the evidence to do so) but what his reign did lead to was apathy and a lack of communication. I remember thinking at that game against Fife that the club was dying on its feet. You would struggle to find a Devils fan who has a positive view of these years. Some of the decisions were plain bizarre, I remember Thomas Kurka, a decent but not exceptional player, being offered 'the biggest contract in the Devils' history', whilst at the same time there were players apparently using sticks that were clearly not up to the job. It seemed a very strange way of running a sports club.
Finally (and I know others have vehemently disagreed in the last few days) the thing which springs to mind is the interaction with the supporter base. Whenever I have asked anyone within the current Devils management and ownership anything in the last decade, i have always got, not just a response but a well thought out answer. I might not always like the answer but I have always respected the answer as there was clearly both insight and sporting intelligence behind the answer. If anyone wants to buy me a pint I can contrast this with some of the points made under previous ownerships
Not sure if that answers your questions at all
@Gisland and I am dancing around some issues but for me the summary is that we went from the lowest point in our history to the highest when our current owners took over.