There are a lot of countries in the data you have posted, that show you are wrong. Spain for example went from 275g/kWh in 2018 to 205g/kWh in 2022. Portugal and Greece did reduce even more in the same time. None have built more nuclear, but they added a lot of renewables. Just as some example and you can find even more. Here is a longer but annual map of carbon intensity were you can see my point a bit better. The issue is that wind and solar have dropped in price a lot in the last decades. In the last one they have become cheaper then fossil fuels in many places, but they cost a lot to install. So grids with a lot of none hydro renewables are rarer. Really important to say is that their are ways of dealing with intermittency. The two main ones are larger grids and electricity storage. In terms of grid size hvdc is falling in costs in recent years, this allows for intercontinental electricity connections with 3.5% power loss over 1000km. So you can built continent wide grids with relative ease and is always windy or sunny somewhere. Electricity storage is pretty obvious, but battery prices are falling fast and hydro power plants can be used for this as well.