How many open bottles is too many?

Been in the stores a lot this week. Might sound crazy but browsing the whiskey section of the liquor stores is relaxing to me. Especially after a stressful day or week of work. I don’t know if shops just picked up their new year deliveries. Got some upgrade bottles of Pipe Dream. Been looking for Elijah Craig Barrel Proof for months and found that too. Even found Emerald Giant for $25. Last stop today I ran into the Coy Hill JD. I asked the cashier how many bottles they got in just being curious. It was the only one. Guess it was meant for me. I saw a single bottle of Remus Repeal that will have to wait until next week. Feel kinda guilty opening anything right now. I got 15 bottles open. Buddy of mine warned me not to open too many at once as the taste changes depending on how much oxygen is in the bottle. Any truth to that?