Having used both a 15 inch and a 13 inch within the last couple of years, I will give the most measured answer: “it depends”.

If you’re lugging the laptop on a lengthy commute every day the I would say that speaks against having a heavier 15 inch. On the other hand if the work requires an external GPU and sustained CPU-bound workloads such that a robust cooling solution is necessary: then 13 inch is probably not a good choice.

I’m definitely not in the same camp as some “road warriors” that don’t use external peripherals though, so screen sizes really don’t matter much: for the work I do (webdev) you’re nuts if you don’t use external min 1440p screens. Also external ergo keyboards are a must in my book. Laptop keyboards are absolutely terrible for your wrists.