It’s also normal to become less accepting of change as you age. I think this has to do with decreasing neural plasticity and the “crystalized” intelligence (accumulation of information) that comes with age even as “fluid” intelligence (processing speed, etc) declines.

Synaptic strengthening happens as you age - you will lose neuronal density, but the neuronal connections you still have are stronger and more efficient. The myelin sheaths around these neurons thicken well into middle age. The distracting neuronal channels, things that didn’t serve you over your years of experience, have died off leaving only the most effective connections.

So, you’re old, you know how stuff is supposed to be. You work well within that framework. When things change, it’s harder for you to keep up with it. It puts your brain under proportionally more load.

So you get mad when the bread aisle moves.