You are mixing integer and floating point formats. That is not valid. 32bit integer might have 192dB dynamic range, 32bit float has an excess of 1500dB.
The advantage of 32bit float is not the amount of bits added compared to 24 bit integer but the fact that there is practically no upper limit for a signal anymore, ie. unlimited headroom. It is not possible to clip a floating point signal.
Philippe had a pretty good description on the difference between 32bit float and 64bit float: