The pre-made components and user lib is huge. I was at Amazon working on something - their own engineer was using draw.io to quickly grab AWS icons for Lambda,

The pre-made components and user lib is huge. I was at Amazon working on something - their own engineer was using draw.io to quickly grab AWS icons for Lambda, IoT core, API Gateway etc and place them into his flow chart. He said they had a library somewhere of AWS artwork, but it was easier to just use draw.io’s art lib.