You must decant.
It doesn’t mean your a snob or a wanker, you don’t have to put your wine into some cut-glass vase your grandad stole from a cruise ship – it is simply the very important process of slugging your wine into another vessel to get some air to it and start bringing it to life.
The aim is to get it completely out of the bottle; taking a cork out and “letting it breathe” is a falsehood. Get big air, as Tony Hawke might say.
If you’ve got a cheap wine you’ll notice decanting it softens all the harsh edges.
And do it with white wines as well as red to wake the wine up.