I think this will be a hit with the big name audit companies. I know some use databricks for pyspark on the M&A side. As deals move forward and they get more data, they have to scale up their instances which isn't cheap. If polars enables serverless compute where you pay by the job, that could be a big win.
And sure, databricks has an idle shutdown feature, but suppose it takes ~6 hours to process the deal report, and only the first hour needs the scaled up power to compute one table, and the rest of the jobs only need 1/10th the mem and cores. Polars could save these firms a lot of money.