laburn

It seems to you what?

Attribution of malware can be difficult and the lack of details like who was targeted and missing plugins don't leave enough information to guess who might have been interested in developing this.

I don’t normally see ARM with thumb code so I couldn’t tell you. I am fairly certain it is supported but to what degree I am uncertain.

I regularly look at ARM software and firmware. There are certain things that IDA does better, like FLIRT analysis, which I’ve missed since switching to Ghidra.

Ghidra also currently lacks support for certain ARM instruction decodings so you can get odd looking disassembly. That isn’t to say you can’t add it.

Ghidra has been very nice for reversing C++ code. After filling in most of the members for an object field it makes reversing other subroutines that use the defined type simpler, IMO.

I don't understand how this differentiates itself from ARM TrustZone.

You can already create a system with a dedicated HSM and run your own trusted operating system using the features of the processor. With Intel SGX you are somewhat stuck with using the HSM provided by Intel. With the BSD-licensing aren't we left in the same place as ARM processors, with the exception of producing a RISC-V processor being less expensive with regard to licensing?

Making something closed source does not make your product more secure, it only makes it harder to look at. Determined people will still try to understand how your software works in order to accomplish their goals.