Having just been to the Canaries (August so warm, no cold weather clothes needed) I overpacked horrendously.
To be fair it was our first family holiday abroad and we were within our baggage allowance etc but I just didn't realise how little we'd wear.
Evening wise I was fine, I packed us approx 6 outfits and we wore them all twice but daytime wear I went way overboard. I expected the youngest to burn through shorts and tops but she lived in her swimmers. I'd taken like 10 shorts and 10 tops and she wore a fraction of that amount (and we did beach days / trips etc). All of us came back with clean stuff.
I also overpacked shoes. I took a pair too many for each of us.
We are away again next summer so at least I can hone my packing skills. Although I suspect next year I'll over pack too 😄
I'm way too used to packing for UK holidays, where you have to pack for every season.
Personally as long as you are happy and able to carry it and it isn't costing extra then I'd say take whatever you want. Much better to have extra than be left rinsing a dress in the bathroom sink.
Of course if you have a washing machine then you can definitely pack on the lesser side. We had 14 nights and no washing machine!!
I do find competitive packing seems to be a thing. The less you need to pack seems to be some weird status symbol?