HarryE: … my reasoning is based on the opinion of an IMEC professor …

We cannot completely rule out that an IMEC professor has its own worldview (or should I say agenda) due to what IMEC is doing, see "Technology Achievement Marks Significant Step Towards Monolithic Heterogeneous Integration and Non-silicon Devices". No surprise if his view of POET is more critical than appreciating!

I would take opinions of IMEC professors seriously, but also with a grain of salt.