If I'm not in a hurry, can I just set a low gas fee and wait for days?

Everyone complains about gas fee, I don't understand if I'm missing something or not.

Let's say I want to transfer some eth from my hot wallet to my cold wallet. I don't care about the timing, I can wait even days.

I noticed in the last days gas fees were 70 Gwei, 100 Gwei and even 300 Gwei.

Could I just send my eth and setting gas fee at 50 Gwei and then wait?

I noticed some apps sends you a notification to alert you when the gas fees are low so you could send money in that moment and save on gas fees, but what's the point? Why not just put the price you want and wait?