A homeless shelter is "meaningless"? Wow. I could understand downplaying its significance (e.g. the leader of a country could do more good with policy that improves his country's economy) but giving people shelter is not "meaningless" no matter how you slice it.
Nothing wrong with a shelter. However the the act of designating the presidential palace as a homeless shelter is meaningless because it a) doesn't actually fix anything (one shelter does not a social policy make and has no wider impact - and that's what national governments concern themselves with) b) there is no good reason to re-purpose that particular building, as opposed to another building or spending a few extra bucks and building another. I may be showing my cynical side, but it seems the only reason this was done was to score some cheap PR points with the voters.
I see the problem. You meant "meaningless" as in "it doesn't tell us anything about whether this person is a great guy or not". I interpreted "meaningless" as in "this act has no consequences and does not actually help people as it intends to do".
The man spent two years in solitary confinement at the bottom of a well. He has a much greater appreciation for simple living than the typical head of state and how even small gestures can mean a lot to people. Using the palace for himself and his family provides far less marginal utility than using it to house many homeless people.
This is is a deliberate decision, not becasue of a lack of resources.