By "techwashing" I mean using some of the money a company makes in its main business (which in the case of Meta and some other corporates has a bad impact on society) to make a positive technical contribution to the public , thus helping existing and prospective employees work there with less of a guilty conscience.

Similar, to e.g. a pharmaceutical company raising the price of a medicine excessively, but then donating some of the money to build a hospital.

It's just that in the case of tech companies, the reputation washing is done via technical contributions.