I hear ya, my minimum all depends on what I'm shooting. if I am hurting for light I'll go as low as 1/160. It just means I can't stop motion. But when birds are in between movements. They are often times stock still for a brief moment. And I'll raise my shutter speed when I want to capture motion.

So I'm not cranking it to the moon the ISO at least as much.

I used to do lots of lower light stuff, but lately I have tried as much as possible to hit that sweet spot in the evening where I get a good amount of light but birds are still active. Same in the morning.

Or depending on my birding locations they will be there throughout the day. So I can have my pick of lighting. This is ideal. I can be using ISO 100 or 200 and get what ever shutter speed I need. Maybe little bit more if I need higher shutter speeds.

Of course, this is just me. And not everyone is me.