Further nit-picking -- I think you should have to have attended a Major League Baseball game at the stadium to count it.
A current HC student who goes to Nickerson Field to watch a lacrosse game against BU shouldn't be able to claim they've been to Braves Field. Same for someone who just went to a Jay-Z concert at the current Yankee Stadium.
Blame me. I'm the one who opened that door, but also clearly segregated the places I've seen baseball from the silly stuff. I even referred to my own Nickerson note as lame
What if you saw the Pats play there in 1962 before they tore 3/4 of it down?
(edit). The next year or two BU played at Fenway while they were tearing the main grandstand down and putting up the 3 high rise dorms. I was supposed to see them play BC there in what was going to be the final game in that series. It got cancelled due to JFK's assassination.
Picking the 70's as an arbitrary not that long ago in the life of a building
The Blue Jays, Twins, Mariners, Braves, Phillies, Marlins, Reds and Pirates all replaced stadiums built in the 70's or later while the Red Sox and Cubs seem to survive in 100 year old stadiums.
Almost all of the stadiums built from about 1964 to 1980 were hideous bowl-shaped football/baseball combo stadiums, and many were almost identical. Terrible for baseball and terrible for football. Often with artificial turf, to make it even worse. Thankfully they are almost all gone now. Although they weren't quite as bad as many on the above list, Busch II and Shea Stadium weren't good.
Wrigley and Fenway have survived because they are true baseball stadiums, as are most new stadiums of the past 25 years.
The only problem I have with what got torn down was that the players are bigger and stronger, the bats are the same strength but lighter, the pitchers throw harder, the ball is (or isn't) juiced; all of which add up to the ball traveling further when hit solidly. But the parks as a whole have shorter field dimensions. Doesn't make sense.