Countries are meeting their renewables targets years ahead of schedule, and the cost of wind, solar, and batteries will continue to decline. I don’t see any way we’re still using fossil fuels for electricity by 2030. It’s not optimism, just curve fitting.
Nuclear advocates have a bad habit of never delivering on time and/or without massive cost overruns. Renewables (solar and wind) are already below 2 cents/kwh at utility scale. They, theoretically, should be considerably cheaper in 5 years (and so, nuclear must target 1 cent/kwh to be profitable).