Every company that can build light tanks will want to have a product on offer. Just that most of them are too risk averse to invest in designing one from ground up.
Critical parts in EVs built by even Tatas and Mahindras come from China via Indirect route to hide actual origin. Such well established companies with good markest share and considerable volumes are reluctant to invest in core R&D for a product which they know will be in market for 10-15 years. Investing for 5-10 years building a complex product that will have to be L1 after it has passed Moon and Mars trials is practically Harakiri for decent sized companies when you know your competitors will simply change name-plate of foreign maaaal and claim it to be made inhouse
Only way to resolve this quandorum is initate a system, where each part in any defence product should come with certification that it is 100% made in India from Raw material onwards. Anything else should have 100% direct additional taxation on import value which should be based on Fair market price (and not bogus low value Invoice that are usually submitted). There should also be a cap of 30% for imported components breaching which disqualifies the company. Creating this breathing space may encourge Indian companies to do actual R&D
Automobiles have strict laws to monitor these kind of false labelling. On the other hand, did you checked the Mahindra EV Launch show, there is full list of supply vendors in that video. These are common suppliers for both TATA and Mahindra.
The main component in EV the battery is sourced from BYD(Mahindra) and Tata Autocomp (Cells are imported from Gotion (Chinese company)). Next part is the motor, both of them using the Valeo motors (German component), ADAS will be from Bosch (Both of them use, heck all cars in India will use majorly Bosch), BMS is from another EV supplier. Especially with EV, it is like assembly of various components.
Chinese companies like BYD, SAIC went with horizontal integration, Tesla does this. Traditional Auto companies generally don't go to this extent except Japanese where they have stake in suppliers also.
Meanwhile in India, we don't have companies operating in critical areas like ECU, Injection system, Turbo charger, Gearbox manufacturers, ADAS etc. We are always depends on German, Japanese, Koreans for this.
What we need is a startups like Bosch, Valeo who can work on component levels. Currently very few companies were operating like this here.