I've read that about wonders before but I don't buy it. I love building them. Worth it for the cut scene alone. I play a long game though. I suppose for the TTW obsessives they may make less sense.
If you are going for speed and finishing fast I don't think you want to focus on Wonder Building.
I think this is more of a game style or preference thing.
I usually stay away from them as I like to capture my Wonders with an Army.
Although I have had some games where I had amazing production and also a 9+ Desert Hill Petra Location.
Kinda just have to build Petra if you have a ton of Desert Hills,
With that map and production I was building 2 or 3 Army Units per turn and cranking out Wonders.
However that is not the normal game I usually fall into.
I find that rolling standard maps usually have a ton of flat land.
I usually have no mountains for faster science adjacency.
My chops are very limited and I usually opt to improve the forests or jungles instead of chopping.
I also have been running into coastal cities where I don't have many tiles to work and I am not chopping those limited trees.
In these games I usually have a close neighbor and I just go full military from the get go.
If everything goes good I usually have 10 to 15 cities by turn 100 which is good for me but better players get more.
I hardly ever go for Religion or build Holy Sites and I think many players fall into that trap.
If you are in the right situation Religion can be amazing but most games I can't risk it.
So as usual we come down to situational gameplay.
Map and Game Dependent as usual.
Some games I just do the wrong things.
I talked about a recent game where I got Double Dowed and they had a sword heavy CS allied.
So it was more like triple dowed.
Now I was being arrogant in that game and was ill prepared.
If I read the situation better I would of went 1 or 2 city with walls and an adequate Army.
I think the main point is you have to have fun the way you want to have fun.
If building a bunch of Wonders is your fun, by all means build Wonders.