You totally can do it with some combination of overbuilding, storage and increased interconnection. It just starts to get expensive the higher the portion of your generation you want to supply with renewables. There's a good Construction Physics article[0] about this (though it simplifies by only looking at solar, batteries and natural gas plants and mostly does not distinguish between peaker and more baseload oriented combined cycle plants).

Personally, while I'm not opposed to nuclear, I'm pretty bearish on it. Most places are seeing nuclear get more expensive and not less. Meanwhile solar and batteries are getting cheaper. There's also the issue that nuclear reactors are generally most economical when operating with very high load factors (i.e. baseload generation) because they have high capital costs, but low fuel costs. Renewables make the net-demand curve (demand - renewable generation) very lumpy which generally favors dispatchable (peaker plants, batteries, etc.) generation over baseload.

Now a lot of what makes nuclear expensive (especially in the US) is some combination of regulatory posture and lack of experience (we build these very infrequently). We will also eventually hit a limit on how cheap solar and batteries can get. So it's definitely possible current trends will not hold, but current trends are not favorable. Currently the cheapest way to add incremental zero-carbon energy is solar + batteries. By the time you deploy enough that nuclear starts getting competitive on an LCOE basis, solar and batteries will probably have gotten cheaper and nuclear might have gotten more expensive.

[0] https://www.construction-physics.com/p/can-we-afford-large-s...