You are fundamentally conflating releasing a binary under an open source license with the software being open source. Nobody is saying that they're violating the license of Apache2 by not releasing the training data. What people are objecting to is that calling this release "open source", when the only thing covered by the open source license is the weights, to be an abuse of the meaning of "Open Source".

To give you an example: I can release a binary (without sources) under the MIT - an open source license. That will give you the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of said binary. In doing so, I would have released the binary under an open source license. However, most people would agree that the software would not be open source under the conventional definition, as the sources would not be published. While people could modify it by disassembling it and modifying it, there is a general understanding that Open Source requires distributing the _sources_.

This is very similar to what is being done here. They're releasing the weights under an open source license - but the overall software is not open source.