Again, it's completely irrelevant to anything at all... just a cheap argument for the Left to try and make, but I'm willing to guess Obama's inauguration was absolutely larger.
However, the photo everyone is talking about was before the prime-time. I've seen another, much-fuller photo from Trump's.
But, talking about it is what they want. Spicer was probably wrong to say it was "the largest", but he's doing what he's told. He's saying what the media wants to hear, and now they're going to be talking about that instead of anything important. I'm very interested to see how far the media is willing to be guided and led from the real news into talking about inconsequential stuff like this.
This is pretty much it. It doesn't reveal anything meaningful. It's soley for the purpose of "neener neener, our guy is better than yours".
ETA: The press went with this early and often. I initially watched the leadup to the inauguration streaming from CBSN, because that stream happened to be most reliable over my connection. Later when I had a TV available, I switched to a Fox affiliate. But CBS dropped some mentions throughout their broadcast. I was like. Wow. I know that they have to fill in airtime, and usually it's with meaningless drivel, but that's kinda petty. And given that it became such a common theme, it seems like someone got the memo.