I'm just learning about a heat pump now from this thread and then reading about them. Do we not already have a way to convert radiator/boilers to electricity?

I'm just learning about a heat pump now from this thread and then reading about them. Do we not already have a way to convert radiator/boilers to electricity? It's just boiling water right. My condo is in a 110 year old building. I love my radiators even if they don't work that great ;) and really would hate those electric baseboard radiators We probably will have to replace our boiler within the next few years due to issues (neighbors are too cheap to go all electric/vehicle chargers with me so no proactive changes). I just assumed we could get an electric version? I would hope smaller and not a giant cast iron thing sunk under the house. Would that not also work for new construction?