Yes cause a MicroSD card that is more expensive (by a lot) than the console itself is totally reasonable? I wish. The solution to this, I've found in my own experience, is to stick with a 80-100 gb sd card, and simply uninstall games after I've beaten them since I've gone digital only. I have blazing fast internet, so if I want to replay a game I just redownload it quickly. This way, I still have all the essential ones that I play randomly or on the go, but avoid the high cost of these newer cards.
You can aim higher by now, I bought an 128GB SD card for my Switch 2 weeks ago for about 17$ (15€) and are generally available for under 20$ without having to search for long. 256GB still costs around 50$, but I'm sure prices will drop to about 30$ until summer/fall.
Anything bigger than that however still seems to expensive to me to be really worth it