Exactly. I'm not sure why this Boldin pipe dream keeps gaining more momentum.
Maybe it's because we have plenty of speed at WR, but we don't have a reliable, physical possession receiver, and Boldin happens to be just that. Also, Harbaugh expressed interest in bringing him back, Ozzie emphasized the need to add a possession receiver, and as of right now, there isn't anyone else out there on the market, so I don't know why you would think it's just a pipe dream.
The better question to be asking is why would Boldin want to come back to Baltimore?
Cuz Boldin and Flacco had a good relationship. AND Boldin is hanging out thee "until after the draft", before he makes a decision where he might go. He liked it here. I don't think he wanted to leave in the first place. He even said he would retire before playing elsewhere. I wouldn't rule it out completely. Like I said #81 just became available again.