I have simple rules regarding weather:
1° it's more than 12-15°C outside : shorts and short sleeves
2° it's less than 12-15°C : long tights and long sleeves
3° it's less than 5°C : add cap, gloves and microfibre top to the previous set.
4° it's raining: I'm not made of sugar :)
5° it's heavily raining : I wear a cheap rain poncho, it's fine.
All my sport wear is the cheapest stuff from Decathlon, 5 euros shirts, etc. The rest of my gear probably cost me less than 150 euros and I've been using all the same gear (but socks and shorts) for 10 years, it doesn't wear out much.
I wear the exact same socks and shoes and short-sleeved running t-shirt whatever the weather is. I only use one sort of anti-friction stuff: 3M tegaderm. Exactly 1 square cm2 of it on each breast. A roll lasts a couple of years or so. I threw away a pair of shorts that hurt me at the thighs. I don't carry any money or phone or anything but my home key, in the small pocket all shorts and tights have. I don't carry water either, because I don't run more than 2 hours straight anyway, I drink before and after and that's fine.
I had a couple of injuries after turning 45 but it's nothing gear-related, really.