Already the case in Europe. And in the US, most of the biggest player are doing this: Google, Microsoft, Meta, AWS. By now those 4 are the largest buyers of renewable purchase agreement in the entire world. MS alone invested something like 20B in renewable purchase.
But the issue is that installation of renewable in the US is not bottlenecked by lack of demand, it's bottlenecked by permitting, zoning issue etc. The queue for power deployment right now is something like 100GW (i.e. how much production is paid to be built, but not yet built), that is around 10% of the current total US power capacity. So it's not really clear to me if buying more renewables helps making it's deployment faster through economies of scale, or if the purchase order is just sitting in a queue for years and years.
One notable exception is xAI/Grok, who has one of the biggest cluster, is powering it 100% with gas and afaik did not offset it by buying the equivalent in renewable. Having built the cluster in a what was a washing machine factory that does not have adequate power supply or cooling tech, they have been rolling in 35 mobile gas turbines (large trailer trucks that you connect to gas pipes) and 50+ refrigeration trucks. IMHO, it should be illegal to build such an energy consuming system with such a poor efficiency, but well.