No question this is true.
Still, in post-season baseball, you get only a few days to prove yourself. Many times, a game will be win or go home. If this is even the slightest problem for a player, I'd rather learn about it during a "tough position" in July or whatever, than in October.
I don't point fingers at any particular player as not being clutch. You can never know with certainty, in part because of small samples, in part because you can't look into the player's soul. Still, the nature of most sports or competitions is that infinite patience is not granted.
The best course for players trying to establish themselves is "prove it." Then prove it again, and prove it again, until the sample is no longer small. Bad luck if they can't, and it's part of the game. The team has provided Roden opportunities against right-handed pitching. Maybe another team finds the treasure in our discards.
You did go on to say much the same, but I think it bears reflection.