Given that the outlook for the foreseeable future is inflationary, parking money in productive land makes sense from a wealth preservation standpoint.
If the government decides that farming generates too much greenhouse gas, Gates is more likely to comply and let the land lie fallow unlike the farmers in Germany and Denmark. Can you say famine?
If investing were his only goal, why the complex network of shell companies with multiple overlapping interested parties and jurisdictions? He wouldn’t do that without a reason, so, what is that reason? Recall that the Bidens set up multiple shell companies, apparently to receive, launder and distribute foreign bribe money to various family members (for whatever reason).