It's not that. It's just that he didn't occur to me. He's pretty anonymous to me. Which again, why he gets no HOF love.

For me, there are other bits with Abreu. My memory for these things isn't great and I'd have guessed he was still on those Howard-Rollins Phils' teams but he was gone by then. Then I recalled how aghast we all were at how little the Phils got in return when they traded him to the Yanks which was part of a big Yanks' playoff push but, although he appeared in the playoffs with them, they didn't make the WS those years either. In fact the closest he came was with the Angels, losing in the ALCS, and I don't remember him on the Angels although he was there for 3+ years nor do I remember the 2009 Angels as a good team (they won 97 games).

It's also because I'm more familiar with this question as "never appeared in the postseason" as opposed to the WS. I agree that both in looking back historically and in adjusting for the fact everybody makes the playoffs now that focusing on the WS is probably the way to go. But, as an example, every Cub fan of my age or older knows that Billy Williams made the postseason with Oakland so he's not on our tragic list but that Oak team lost to the Red Sox so he didn't make the WS.

Billy played 16 years for the Cubs, then joined the A's as their DH the year AFTER they won 3 straight WS.
went 0 for 7 in 1975 as the A's got swept.

so played in the postseason, but never won a game - nor got a hit.

1975 A's were kind of wacky - teammates included, beyond the well-known A's, Tommy Harper, Cesar Tovar, Dal Maxvill, and Billy Grabarkewitz.