So as long as you need anything more than just a constant frequency blink it will actually be cheaper to use a tiny 6 pin MCU, also its more compact. I went down the path of designing an analog circuit for a easy task, only to get half way there, realize this takes a lot of components to do properly, then throw it away and replace it with a MCU.
You can't get much cheaper than a Schmitt trigger IC, such as the 74HC1G14 + RC circuit and costs less than the cheapest MCU, in small quantities.
If all I wanted was a flashing LED, just use a self-flashing LED: no discrete components, or coding required!
I remember seeing flashing red LEDs in “Tandy” in the UK, back in the 90s, for about £4, and I recall thinking what a ripoff it was 😁
It was, but they’re great.
Everything was expensive in Tandy. Basic components, such as a plain old TO-92 BJT, 741, 555 timer etc. cost around £1 each. They used to be sold in blister packs with the component sealed inside a vacuum formed bubble, stuck to a piece of cardboard, with a basic datasheet printed on the back. Worse still, the packaging wasn't even ESD proof. I'm pretty sure I had bought faulty components from Tandy, but as I was only 12 at the time and a complete beginner, I didn't have the confidence to complain, as I thought it might've been my fault.
I remember seeing a few empty packets in the store. Either someone had stolen the components, or the glue had started to fail, allowing them to fall on the floor and presumably vacuumed up. They probably lost as many parts, as they sold.
I remember discovering Maplin, which was much cheaper and sold a greater range of components, but there wasn't one in my town, so my dad occasionally drove me 10 miles to go there. Eventually a Maplin did open near me, but by then Tandy had gone and it had deteriorated to the point of being useless, for most things.
In Oz, sometimes Tandy would have some weird bit that nobody else had, but at an exorbitant price, or other times, it was just easier to "bite the bullet" & pay up for a common component, rather than drive a couple of suburbs away to Dick Smith.
On the former point, the bloke next door came over with his daughter's intermittent car radio for me to "take a look at".
All pretty standard, except for a largish DIP audio amp IC, which turned out to have a temperature sensitive fault, & more importantly, was "unobtainium" in Oz.(this was pre-Internet!)
After looking everywhere, I was just about to give up, when whilst browsing in Tandy, I saw an audio IC in a vacuum pack, that someone had put on the hook with the cardboard back, showing a suggested application, facing out.
It was "near as dammit" the same as the one I needed, except in a totally different, single inline package, with a heatsink tab on top.
As luck would have it, there was enough room to attach it to the radio's side panel, & by using a bunch of conductors stripped out of a multi cored phone cable, I was able to do a reasonably neat job of connecting it up.
It went "first go"---no more temperature sensitive failures.
No more "Mr Fixit" for me, either, I pleaded too much work from my real job!