256GB SanDisk Ultra Class 10 A1 microSDXC Memory Card w/ Adapter Expired

Now that is funny. The Samsung page has a picture of a guy holding the card in front of a phone like that is what it is for. But Samsung had removed expandable storage. They should pan out so you can see the guy cursing.

If the primary purpose of the card is 4K video, I'd go for a U3 card. This U1 would probably work, but depends on the quality level of the video. For a few bucks more, you can get a high quality U3 card. Here is a Samsung Evo select U3 card for $27 on Amazon, but you may want to buy direct from Samsung to avoid the Amazon fake problems.

SAMSUNG EVO Select Micro SD-Memory-Card + Adapter, 256GB microSDXC 130MB/s Full HD & 4K UHD, UHS-I, U3, A2, V30, Expanded Storage for Android Smartphones, Tablets, Nintendo-Switch (MB-ME256KA/AM) https://smile.amazon.com/dp/B09B1...JTWP9NZ0SZ

This will work for the switch.

Whether it's big enough - depends on the kind of games you play and how you play them (I.e. are you going to be playing many of them concurrently). Another consideration is if you have data caps or slow internet. Typical sizes for console or PC games range from 20GB to 100GB. But for the switch, typical sizes range from 5GB to 30GB.

For example, my use case -
Personally, I'll be putting in a 256GB card on my 256GB steam deck (hoping to get my invite soon). I almost never play two AAA games concurrently (even if I do play games concurrently, the second one is usually a smaller indie game). And so this config will give me enough space to download 3 to 4 AAA games or many more smaller titles. More than what I need. I only play single player games. After I'm finished with a game I delete it and never look back.

I put a 128GB on my switch but it was a waste, as it has always had 0 games on it. I tend to buy more expensive switch games on cartridge and the digital purchases are usually smaller in size. Never filled up the internal storage. Also, I don't have data caps. So even if I ever have to redownload the occasional game, it's not that big a deal.

But that's my use case. For my use case, 256GB is more than enough. Look at your usage and avoid overpaying for storage that you are unlikely to use. Cards are always getting cheaper. If you are unsure about how much you'll need, stay conservative for now. Later if you decide it's not working out you can always buy another low capacity card for cheap. Swapping cards is not ideal, but hardly that big an inconvenience.