> and that nuclear makes great baseline power generation.

While it is true nuclear power is great for baseload power generation. Sadly, that is a nice way of saying this form of power production sucks at load following.

Which is a problem in grids with sufficient solar and/or wind doesn't need baseload power production. It require complimentary power supply/production.

Sufficient, meaning enough VRE to there being enough variable production that there at times the full power production of the nuclear power plant isn't required.

For energy consumption (whether green or fossil or somewhere in-between), speed doesn't matter. Energy consumption is dependent on work done not how fast it is done.