Those look pricey for something that's going to be abused a bunch.

We got a ukulele for our child...we did try with a $20 kiddie uke, but it sucked and didn't stay in tune...ended up with a "kala waterman" one, it's $45 on amazon, and is a legit instrument that happens to be kid sized.

It's not a string instrument, but we also got our child a Yamaha YRS-20 recorder, which is like $6, and that gets far more use than the uke...but the uke still gets a fair bit of play, especially when my wife is playing hers.

I don't know that I'd bother with a string instrument if none of the caretakers play...without at least some modeling, it'll just be a toy/random noise (this may be different if the child is specifically asking for that instrument and has made a plan for how to learn to use it). A piano/keyboard is a bit more straightforward (we got a full sized keyboard, and some music books with the note names listed, and stickers for the keys that have the note names, so the kid can at least play something like mary had a little lamb, etc) -- this was much more pricey than those guitars, though.

For instruments to use without parental guidance, then percussion instruments can be great.

Some of our favorites:

Most likely to make something resembling music without guidance: Steel tongue drum -- https://www.amazon.com/gp/product/B08CCXTY45

Decent quality drums, if you can tolerate the noise: the Remo kids series -- https://www.amazon.com/gp/product/B0002F7KU

Shakers -- make your own with a plastic water bottle and beads, or buy something like: https://www.amazon.com/gp/product/B00BSWTK3C