@yjf - Exxon and Mobil actively embarked on separate ventures to go into new business areas. For example, Exxon went into computers and batteries, Mobil into plastic consumer goods. Both made a complete hash of it, because they didn't understand the markets in which they were trying to compete. The leading people from Exxon's battery technology team left the company and found successful careers in other industries and in academia. Mobil sold off their consumer goods business, with the most successful products now being marketed under the "Hefty" brand.
Please don't kid yourself that "the algae and CCUS seem like the kinds of technologies that use EM's strengths, and so quite a reasonable approach to take". These projects do NOT rely on in-house expertise - CSR is completely reliant on 3rd party knowledge: Synthetic Genomics for algae, Universities and Global Thermostat (the least successful specialist company in this area) for carbon capture.
@xms - it's not just Trump voters. The Brexit vote in the UK was the same. When you lose all confidence in the integrity of the government administration and realize that all career politicians are the same (corrupt and in the game to amass personal fortune and power), all you can do is vote for somebody from outside the system or vote to leave the system altogether.