What is RBI pushing Tata Sons to do and why does Tata Trusts oppose it?

The RBI is pushing Tata Sons to launch an IPO and become publicly listed to comply with regulations for upper-layer NBFCs and improve financial transparency. However, Noel Tata-led Tata Trusts, the majority shareholder of Tata Sons, opposes the listing, saying it would "destroy its character". The Tata Sons board reportedly approved plans for the IPO at its recent meeting.