Dylan became his parents
If you watched any of the reboot "90210", Dylan became an absentee father. Just like his parents were never really in his life, he couldn't be bothered with his son.
The reboot was mistake--it was attempt to create 90210 the next generation. And now that they are bringing back the cast (well most of it) who did launch the series....there is confusion.
The writers of the most recent incarnation had no clue what had transpired. Dylan being absentee also would not fit in with his working @ a community center--which he was @ last season of the original series. The writers did not watch, care to watch episodes for continuity. Putting it on another network gave them an excuse to do whatever they wanted to/with the characters
I think like the ghostbusters remake, it is going to be forgotten.