I started a very successful furniture business in Mill Valley Ca, with nothing but my fathers crappy Crafstman jigsaw, and a surform for rounding edges. I used this jig saw and hand filed, sanded the edges of my first year of furniture making. I eventually moved my shop to Sauasalito. This was 1972, and I have one of my original chairs - it's a bit embarassing as the finish is crude, but tmy furniture rustic as it was sold well enough until I learned how to do woodworking. Then I learned how to join wodd, and do fairly nice woodworking. I was not an accomplished woodworker, just had some cool designs. I still use jigsaws to cut a lot of different wood projects, as my battery powered Ryobi can cut through a 2X4 through the 4" side without going out of plane. It keeps me from hauling around my mitre saw.
If I were building a house, I would choose a skill saw, but I did build a two story house with my crew using nothing but a hand saw. We could not get temp power for 3 weeks, and generators were not readily available. The power company came out and took pictures of us building with just a hand saw, but didn't hurry to give us power. We framed the house and dried it in in about two weeks with me sawing every stud, joist, and plywood piece of wood.
I am not crazy about using human powered hand tools, but I can use them. I admire people who can chop a bowl with an adze