Instead of buying Western planes, Aeroflot should've leased these so as to be able to get rid of these once issues in domestically-made aircraft got solved. It should've simultaneously pressured and consulted Russian manufacturers to produce overhauled/refined/updated versions of their existing aircraft as a short-term solution and all-new, world-class aircraft as the long-term solution.
Aeroflot's switch to Western-made planes [link 1, link 2, link 3, link 4] has been one of the major factors in the demise of Russia's aircraft manufacturing industry. Aeroflot shouldn't have switched completely to foreign-made planes. It should've retained at least some Russian-made planes [perhaps the Tu-204 or An-148] and should've maintained these well.