First off, you are not equating two equal concepts. The two Churbanos did not happen slowly. The Chato’im built up slowly. Definitely the Ge’ula is also a culmination of Zechusim.
Second of all, the Moderator was actually refering to a Gemara in Eiruvin which says that if someone accepts upon himself to be a Nazir on the day Mashiach comes, he may only drink wine on Shabbos because otherwise any other day he might come or in fact have come.
Another point to keep in mind is that the Churban was a natural thing that Hashem allowed and arranged, but the Ge’ula is an unnatural thing. The Maharal explains that when help comes from that level it comes in one shot, because the nature didn’t produce it so it doesn’t need time, which is nature’s way of getting things moving.
The events you refer to are what lead up to make the situation ripe for Mashiach to come. In that sense all of world events in the past were part of that lead up.
There is a Medrash that says that the year that Moshiach will come, the Yidden will be saying, the world is going on as ever before, can it be Moshiach will come this year?
As you read in that article, with our Zechusim we can hopefully speed up the process. But in either case the actual coming is not a natural and slowly gaining process.
If you are able to, you can learn through the Maharal’s Netzach Yisroel, which is a Sefer all about the Ge’ula.