I disagree, especially based on my reading, and especially for your comment about the part where suggested solutions are rejected only based on single testimonies; it's the reverse to be honest, we're talking about essential technologies to avoid a high likelihood of human extinction being considered as available or soon-to-be-available in IPCC projections when they haven't even been experimented on at scale (after political, not scientific, editing, I might add - we had a leak of the pre-politically-edited IPCC report a few months back and it was much clearer about the risk of extinction) - and the smaller scale examples of BeCCS that have been tried, for example, reek with issues. This fight is against the law of thermodynamics. We've released tens of million of years of bio-accumulated solar energy in the span of a century. Even assuming nuclear fusion was practically suddenly available tomorrow would those routes seem extremely doubtful according to the IPCC scenarios in terms of time available, due to the infrastructure/deployment requirements. And this is time we already burnt. And we do not have energy-harvestable nuclear fusion right now (we could have, though, had we actually spent resources seriously on it 40 years ago; perhaps if the USSR had not died).

Ultimately though I think your comment has a better outlook than mine, and is definitely a positive thing, thank you. Nothing is ever hopeless. We live in a wonderful chaotic universe and there may be a black swan event. Even if not, there is still (limited IMO) hope that personally I cling to for some sort of global collapse without extinction followed by an awesome communist society to come centuries from now, having learnt The Lesson. I might add the author himself said they planned to post a "what to do" further article; ultimately the aim is not hopelessness, but realization of just how much more direr than usually described the situation actually is.