Actually there are many buildings named after congresscritters before they died. Robert Byrd had quite a few as I recall.
The actual legislation too - Pell grant, Stafford loan. It’s a bad practice though — in the case of the latter two, it implied the money was coming from the politician rather than the taxpayer.
I can see it if a is a private building and people actually donate or cause the raising of it.
For instance if a philanthropist works for and donates to a building based on some great cause.
But taking a vote and naming a building after a political figure while alive - it’s abusive and indoctrination.
Plus you never know what will happen in the future.