The point reset thing is... complicated.
Now, obviously it's not fair for it to be reset for the 4 servers that were merged up. But it would have also been unfair if they were not reset.
Fact is, being the 4 oldest server in your bracket, chances are you guys occupy a large chunk of the high ranked players, gathering a large amount of points. Let's say there 40 of the top 80 in your old bracket is composed of player from those 4 servers, which isn't unrealistic. Those 40 would, therefore, have more or less the same number of points as the player in the top 80 of the new bracket, in other words, more than the bottom 40 of the top 128 of the new bracket. And therefore, if you guys kept your points, you would have bumped 40 people or so off the top 128 in the new bracket, people, who by virtue of being in top 128 in a bracket where every server is older than yours, that are probably stronger than most of the 40. That would have been unfair too.
So whether you guys kept your point or not, if you guys gets moved a bracket, it will be unfair to somebody.
That said, this problem would have been mitigated if it was done at a different time.
First, if it was done at the start of a season, when everyone was "fresh" so a point reset does nothing. This would be ideal. Of course, this season's ranking battles overlapped with last season's final, and there might be logistical issues with being in the ranking of one bracket but the final of another. Thou I suspect that this is due to the fact that the feature was introduced in the middle of the month and will not be an issue in future seasons, each season being one month with half month of ranking and half month of final, no overlap needed.
Or, alternatively, if there are more days left to go, there could have been a reasonable solution. Give all players of your server a fixed amount of "starting points" that's equal to the point of the say 100th ranked (by point) player of the new bracket. This way, for however many days left, people would have a reasonable chance of fighting it out for the last 30 or so spots in the top 128 in the new bracket. This should reasonably select the best out of all the players in the new-new bracket for the final. While it's possible that of the movers, someone who could otherwise placed in the top 20 (via super ptw) is now merely a rank 90-100, fact is that all that matters is actually reaching the final and exact placement don't matter if you do, so all is well.
So timing could have solved so many problems.
That said, some player feels that moving a server to a different bracket is unfair in and of itself. Well, my opinion on this is "sort of". The part that is unfair, to me, is the whole mess it can create when it is done. However, fundamentally speaking, moving a server from top of one bracket to the bottom of another is fair. Fact of the matter is, no server really deserve to be always on the top or bottom of the bracket, having a server stuck in either position is what is truly unfair. If true fairness is to be concerned, the the bracket should shift every season so that the separation point is constantly changing so that no server, except the oldest server period, will ever always be on top or bottom. So you really shouldn't complain about shifting bracket, because all that does is show your own selfishness.
That said, given the problem that could come with shifting bracket, as evident by this episode, it really shouldn't be done unless Oasis had a watertight procedure that can be followed. As it is, this is an epic fail.
As far as "solving" the problem goes. Unless they can split the server, at least until end of the "season"(potentially post season), the best is probably handing out reasonable compensation to the 4 servers to the players who WERE in top 128, different comp depending on the exact ranking. Fact of the matter is, given the tiny amount of time left, there really is no truly fair way to solve the problem, as giving points to the player of the 4 servers so that they can get to 128 will certainly bump out others from the new bracket and there simply isn't time for the "system" to "right itself" so that only the truly qualified gets placed. So instead of bumping people from a lot more assorted server and spreading the problem in cascading failure fashion, limiting the damage to a fixed population in order to more easily hand out compensation is probably the better solution.