Two of the renewables are intermittent: solar and wind.

They only provide energy some of the time.

That means that you need to have something else to step in when they aren't providing energy.

We don't have the capacity to just store all that energy when they are outputting power to fill in those gaps. Batteries aren't even remotely-feasible. Pumped hydrostorage is our best option, but you can only do that in places with favorable geography.

What it generally means today, in practice, is that if someone is using solar or wind, they used to use coal and now use natural gas to fill in those gaps. If you use solar or wind, you're also tying yourself to natural gas.

For a number of places, if you're using natural gas, you cannot pipe it in. Like, take Guam. They're a little island out the middle of nowhere. They can't pipe in natural gas, need to have it converted to LNG so that it can be shipped in. Europe has some natural gas, but less than the US, and unfortunately two of the convenient neighboring places to get it that might pipe it in are Russia, which promptly started using said pipelines as leverage, and Africa, which has countries that would like to sell it to Europe but suffer from political instability.

If your natural gas pipeline gets too long, then LNG becomes more-efficient. LNG has something like an IIRC 30% overhead to liquify it, but once you do that, you're mostly done. With a pipeline, you have to keep pumping it to keep the gas moving. There's a break-even point where LNG becomes more-efficient if you have to move it further. I looked that up at one point, and IIRC, even security and practicality issues aside, it wouldn't be economically-viable to run a trans-Atlantic pipeline: LNG is more-energy efficient, because the distance is so far.

Hydroelectricity is renewable and doesn't have that problem (well, barring extreme, extended droughts, but it comes with a lot of flexibility in generation), but it's limited by geography; you can only put hydroelectric dams in some places. Also, there are some people who get upset about the ecological impact on rivers, since it changes whether fish can go up and down the river and when and how much water flows.

Geothermal power is renewable and also doesn't have that problem, but is also limited by geography.

With nuclear, you've got a raging anti-nuclear crowd.

EDIT: One point in LNG's favor -- I went reading about current LNG systems a while back. They're...presently not very efficient, and it'd be possible to do engineering work on them to improve efficiency. Basically, if you're liquifying LNG in the US and shipping it to Germany and then regassifying it, you're running what amounts to a gargantuan air conditioner compressor. You're making the gas very hot in the US, then producing very cold output decompressing LNG in Germany. Right now, the heat and coolness on each end are "thrown out", not used for other processes, which is why there's overhead. So, IIRC Germany is (or was during the crisis, dunno what's going on now) using floating LNG regassification plants, things that are basically converted LNG tankers. Those things deal with all the coolness they're generating by having their LNG regassified by dumping it into the water. So we're spending a lot of money and energy to heat up water or air or something in the US and then chill German port waters (in fact, I was reading some article a while back that people were a bit worried about the ecological impacts of the chilling). It'd be possible, if you were going to use LNG, to reuse some of that energy, which would avoid that waste.

In California, part of the California State Water Project involves pumping water up over the mountains to where it's needed. That costs energy. But it's set up to recover some of the expended energy by having the descending water drive hydroelectric power plants. Same kind of idea -- you can refine the process to eliminate overhead.