I taught myself QGIS for spatial analysis of map data-- coming at it from a coding perspective. It has great Python integration. It's also surprisingly useful as a spreadsheet alternative for certain tasks because it supports a SQL-like interface into CSV data, so you can join CSVs with spatial data or with each other, create views and virtual fields, and so on. Overall, very impressed with the depth, breadth, and ease of use considering how powerful it is.

I used to work at an ISP based in the UK. They also put fibre in the ground. Their entire "design" tool was basically a huge QGIS python plug-in.

It is incredible the flexibility QGIS gives you. By paying a couple of developers the company probably saved millions in software.

Check out Atlas.co - kind of like airtable but for spatial data and spatial tools

its good for teaching, otherwise it may be super clumsy with large layers and this is unsolvable in the near future. ref. ticket.

even so, we must admit, is still the most comprehensive opensource something to compete with esri.