No other project can handle 4000 tps decentralized (as it is running right now on the testnet)
Yes, I agree but you said now and who knows what will be in the future. I think some projects will go well beyond this level still being "blockchain" and open source.
You can't expect a project build on top of a blockchain technology to have 4000 tps. It's achievable only if it has either a low number of full-nodes (which leads to centralization) or off-chain transactions (which leads to insecurity in general). Some developers move to DAG, but it still has some scalability issues.
I may be wrong, but as far as I know, Radix is going to become opensource in a year or so once the project is released to the public.