I have been knitting for a long time. When I was a teenager I sewed my own clothes, including my school skirt, and knit my own jumpers. I once went to a wool party (yes they existed) and bought some icelandic lopi wool. By the end of the weekend my dad had a bottle green yoked sweater with grey and red colour work around the yoke and cuffs. Just like that.
The LYS sold Phildar. I thought nothing of taking on complex lace jumpers in lace patterns with unusual shaping. I remember the beige and brown lace sweater knit in mohair, silk and something else. It had a scoop neck and a rib collar. It was beautiful. I didn't consider that I couldn't do it. A lot of that Phildar yarn was very fine - never put me off. Sometime things were a disaster - the pink and purple star yoked sweater would have fit a yeti - I never worried about gauge. But I wore the thing anyway, with pride. (It looked amazing with the stripey dungarees I made and the red suede fringed ankle boots).
Now, I look at patterns and think that maybe I would never finish the colour work or lace jumper. Or I question whether I have the skills.
May good things come with age - but becoming fearful is not one of them.