Onshape is nice and I enjoy using it, but the free tier has some really absurd caveats that anyone considering the platform should be aware of:

Free users are restricted from commercial use and all designs are publicly-available.

Additionally, while free users technically continue to own the IP they create, they lose control of licensing rights. Section 1.7.2.2 Your content - Intellectual Property of the Terms of Use states

For any Public Document owned by a Free Plan User created on or after August 7, 2018, or any Public Document created prior to that date without a LICENSE tab, Customer grants a worldwide, royalty-free and non-exclusive license to any End User or third party accessing the Public Document to use the intellectual property contained in Customer’s Public Document without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Document, and to permit persons to whom the Document is made available to do the same.

In theory, this means that while free users cannot monetize designs they made on the platform, paid users can take those files and monetize them without the consent of the creator(s).