[15] McKenzie-Jackson grew up a vegetarian on the grounds of animal welfare, “At 14, I transitioned to veganism, which helped me understand why it can't just be personal change when fighting the climate crisis”.

The collection "The Mockery of Money Behind Destruction" aimed to increase public awareness of how the oil industry's revenues are used to fuel the global warming issue.

[30] On 20 September 2019, alongside UK Student Climate Network, he managed to break England's national record for the biggest environmental protest [31] with over 100,000 demonstrators in attendance.

[32] In November 2019, McKenzie-Jackson went on an expedition into the Amazonian rainforest,[33] where he learned about social and environmental injustice and he met with well known activists such as the Pussy Riots and Chief Raoni.

In July 2022, McKenzie-Jackson and his partner, Jerome Foster II, co-authored a letter to the UNFCCC to call on the United Nations to move COP27 climate summit due to Egypt's "LGBTQ+ torture, woman slaughter, and civil rights suppression" he says[47] after they started looking into logistics of traveling to Sharm El-Sheikh.

The letter, which was directed towards UNFCCC Executive-Secretary, Patricia Espinosa, was signed by prominent activists such as Nadya Tolokonnikova, Ahmed Alaa, and Eric Njuguna.

The couple are calling the UNFCCC non-action a betrayal of the community and “inherent discrimination.”[50] McKenzie-Jackson emphasized that, “there are better options of countries in Africa that will still include African voices.

I'd like to see real action, following science, while treating climate change like the crisis it really is.”[52] Mckenzie-Jackson is bisexual and has been in a public relationship with his partner, Jerome Foster II, since 2021.