Intel's biggest hurdle is going to be perception.
With enough time, talent, and resources anyone can create a competitive GPU. And manufacturing costs are relatively equal across the board. So on paper it should be relatively easy for Intel with it's cornucopian resources to enter the GPU market.
But it really doesn't matter how good a product is if people don't believe it's good. And Intel has a long history of producing barely adequate graphic solutions to overcome. It's kind of how AMD painted itself into a corner by being known as the price performance king. Making it really hard to offer a premium product at a premium price point. They didn't even bother going after the 2080 this generation.
The only way Intel has a fighting chance IMHO is they need to use the same strategy Nintendo has when going up against the two major consoles. Produce a product that fills a unrecognized niche' like they did with both the Wii series and the Switch. But is there really any value added niche' in the discrete GPU market?
They could of gone after ray tracing and if memory serves at one time were seriously considering just that, but never went anywhere with it. After ray tracing what unique must have feature can they offer to drive sales? I can't think of one. So even if Intel can bring a competitive product to market it most likely won't be enough.
They can try undercutting the market. But as AMD has shown that's a duel sword and can actually hurt as much as it helps. Plus Nvidia and AMD have been playing in this chess match for decades and know every counter strategy available. Sure a price war will benefit us consumers, but will it benefit Intel? Considering its a public company, only for a short time and then the certain loses will force it to exit the market.
To actually move the needle Intel needs not just a competitive product but one that crushes the competition. Giving consumers no choice but buy it. Truly viable real world 4k and ray tracing at the current market price point would do it since both haven't really matured to the point where we see the benefits marketing hype says are there.
But is it possible? I really don't know TBH, but I doubt it. If Intel can show a sub 1,000 dollar card running a AAA game with ultra graphics, 60+ FPS 4k, and fully utilized ray tracing, then yeah they can. But that isn't a low bar to jump over, so I personally see Intel entering the market and then exiting it in a couple of years due to not capturing a significant enough portion of the market.