Sure, if a technological solution like a vaccine gets developed I'd be optimistic (cold fusion?). But I currently estimate the probability of that really low.

What made me pessimistic about climate change w.r.t. COVID-19 was that most countries only did something once the population was sufficiently affected, even when the consequences of doing nothing were perfectly clear and immediate. W.r.t. climate change most countries won't be affected much or it will be hard to attribute to climate change and the consequences will be hard to predict and delayed.

COVID-19 was the easiest case of a global tragedy of the commons problem and we failed w.r.t. to a globally coordinated solution. Climate change is much harder. Doesn't give me much cause for optimism.