I theory, you do have a point.
However, what we tend to see is that the main reason for not wanting to work with us is because of a lack of technical expertise.
We require manufacturers to provide us with a fully working BSP, that they have to maintain. Being able to do so shows prospective buyers they have the expertise and the commitment to support the product, and allows us a direct channel back, so we can translate issues reported by end-users to a technical description their development team can understand, so the issue can be fixed.
Most of these brands are "OEM box movers", they don't have any technical staff at all, and either use drivers supplied by the OEM manufacturer, or pay a third party to supply / maintain them. Which they are very reluctant to do. What they have they throw over the wall to the likes of OE-Alliance, and let them create a BSP for it. With no service and support whatsoever. Note that not all should be tarred with the same brush, like with everything, there are positive exceptions here too...
So no OpenPLi image also means you're talking about a vendor that perhaps find its bottom line more important that its customers. Which doesn't really inspire any confidence in the product and its after sales service.
Currently in use: VU+ Duo 4K (2xFBC S2), VU+ Solo 4K (1xFBC S2), uClan Usytm 4K Ultimate (S2+T2), Octagon SF8008 (S2+T2), Zgemma H9.2H (S2+T2)
Due to my bad health, I will not be very active at times and may be slow to respond. I will not read the forum or PM on a regular basis.
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