Granted that there will be some impact on the MIMO from the Iot device, but it will be lopsided as the MIMO can null out the IoT transmission. It can be looked

Granted that there will be some impact on the MIMO from the Iot device, but it will be lopsided as the MIMO can null out the IoT transmission. It can be looked at in a couple of ways: the IoT is having to spread its power more thinly than the MIMO, so the IoT tx will have less influence on the MIMO receiver than the MIMO tx will, or the MIMO's spatial coding gives a degree of isolation which benefits both the IoT and MIMO devices. There will be a problem if there are a large number of close by IoT devices up against the MIMO, as their smallish contributions will sum up to something big. In that case the MIMO would need to improve its isolation from the IoT device by increasing its number of antennas or the quality of its processing. As a side issue (doesn't really negate your argument), excessive transmission power is a cost for battery powered devices, so at least some of this IoT devices will be motivated to use their transmitted power more wisely. To raise a new front in the argument :-), there is a case to be made that the ability of a device to cause interference isn't actually dominated by the power of its transmission, but by the information content of its transmission. Low information content means the signal is easier to predict and a smart enough receiver can predict the signal and cancel it out, leaving only the desired signal.