It wasn’t unilaterally Stalin and he wasn’t wrong that the Marshall Plan was in part designed to blunt Soviet influence in Europe. The Soviets were invited, but the Americans offered conditions they knew were likely to be rejected, such as giving the US a lot of control over how aid would be spent. Plus, the Republican controlled Congress of the time would not have approved of billions of dollars going to communists, even if Stalin agreed to US conditions.
I wouldn’t contrast the Marshall Plan too sharply with Afghanistan. The Marshall Plan was still a loan that had to be paid back, required purchasing US goods with the money, and came with many American business executives to oversee its implementation. Not only that, but this money was given to a business/political class that had very profitably collaborated with the Axis. Even the democracies in Europe had restrictions placed on them (like Afghanistan) to ensure people wouldn’t elect the communists.
