This is good advice. Tinkercad is hardly more difficult than Microsoft Paint and can be easy enough to start doing some basic DIY modeling in an afternoon.
I don't think it is. It starts with the design phase, which is arguably the hardest part, especially if you have no clue how printers work. It's much easier to just start printing pre-made stuff and then learn how to design your own, also taking inspiration from the stuff you've already printed.