I don't know if I can apply that statement to most converts, but I can certainly think of a half-dozen I know in my own life. Anecdotal evidence can be found all over the Internet.
I think there's an honest critique to be had about how Americans boutique -- to use that sometimes offensive term -- their religions, and I think popular lay apologists for both RC and EO exacerbate the problem by acting like they have flawless arguments that will erase all faith-doubt once someone is confirmed. But anyone who has ever been on an extended vacation knows that the longer one stays in the boutique, the less magical it is.
Even beyond that, I think there's a generational characteristic involved. Millennials (in this case I mean those who were teenagers in the 90s) like to impulsively get neck deep in something, find a reason to become disillusioned and then walk away. Since we've been trained to treat religion as a consumer exercise, if it isn't giving giving the expected pleasure one wants from buying in, you stop buying it.
One of those millennials here.
(I hate that term too and what it implies and am thankful to not behave as other millennials do.) And a recent convert too!
You are touching on certain points that I think are correct, from my own experience. I come from a Protestant background, and it was basically nothing to go between churches based on how "well" the pastor did, if their friends were there, etc. This was all ages, but I was seeing it more in those my age or younger. However, and this was interesting to me, many churches were yielding to it to "keep the numbers up." They would introduce things such as "modern worship" services with rock bands, have yoga classes, outsource coffee stands for the entrance, have day care (not Sunday school), etc. Very much a "consumer" focus and what the church can do for "me" and work for me.
I longed for and prayed so hard to find truth, and that path took me through an Episcopal church and a Catholic church, but I had many qualms too with them and eventually arrived at an Orthodox Church. Small congregation, but the most faithful I had been around. Yes, I was "shopping around," but more than that, I wanted to find something "right." I wanted my church to give me the tools to make me work on myself and change me, and I think that attitude is different than other millenials who want things done their way. I also wanted to be somewhere where I felt I was doing something for God, or at the very least participating in worship with His presence there. So, I think part of it is attitude and I pray that many adopt the right attitude. But, there are those earnestly looking out there for real Tradition, and we can't eliminate how important that is.
As it relates back to the topic, what made me visit an Episcopal church was that the traditions seemed older, the sacraments meant something, and it felt more traditional than having a rock band play at you. The Catholic church I then visited was actually far less traditional and a lot more like a Methodist service. I then went to another and it was about the same. I never went to a Lutheran church to know anything about that. I just found it interesting that the Episcopal service was more "high" than either of the two Catholic services I went to. I did a lot of reading too, and came across some great authors on both sides (N.T. Wright, Henri Nouwen), but based on the actual experiences I had compared to what I read (and even read online, not just books), I never felt that it really matched the reality. But, it is part of my journey getting to where I am now, and I am at least thankful for having seen what it is like!