Demographics are a curse for India like it is for China due to their sheer scale. The reason why China has trouble transitioning into consumption economy is because after 30 years of incredible growth, 600M people still subsist on poverty level income. Why? Because at it's peak, manufacturing "only" employed about 1/3 of the country since 1/3 essentially maxed global demand. This is despite massively exploiting the model that made Japan, South Korea, Taiwan rich, and basically surpassing these countries in pretty much every industry except semiconductors. Populous countries has to do proportionally more to to meet it's peoples needs. Sometimes seemingly impossibly more^.
The next 20-30 years is going to be India's peak demographic dividend phase assuming population stabilizes. While there's going to many positive developments, much of it will be squandered simply because India will take ~30 years of incremental growth to get to where China is today, unless it can execute central planning better than the CCP. Otherwise they're left with a bunch of discontent and destructive youth which is much more dangerous than China's curse of unproductive elderly. Growth will also be undermined by automation, which has eliminated entire high employment manufacturing opportunities, while increase in industrial robots is helping existing manufacturing countries retain their base, i.e. China is installing 150k industrial robots per year (3x more than 2nd place) and rapidly climbing the robots per 10k employee metric (Korean leads with 700, China 100, India 5). Further China has massive influence on where manufacturing logistics, they are in a position to pick winners and losers if they ever want to weaponize export controls. And western companies will think twice about repeating practices that allowed China to grew that big in the first place. Development is going to be spread across South Asia, ASEAN, India will not be in a place to capture as much of the pies as China did. I do think it's about time India shapes up and make an concerted effort to develop, but she has accrued so many nerfs for simply waiting too long. It's overdue, but in many ways it's already too late.
^Keep in mind development, especially for a massive potential powers like India is much more involved. There's a reason US pivoted to undermine China after Made in China 2025 was announced. These are industries essential to self-sufficiency AND climbing out of middle income trap, but simultaneously erode US/Western lead. India will face the same resistance if she ever reaches that far, otherwise all she'll ever be is farmers and widget makers. Hegemony will always cap the ambition of potential rivals. It's different for smaller countries are allowed to grow rich, often with support, because they will never be threats. It's why India & China has their own nuclear and space program. Why China expends vast resources for indigenous military. Once India grows too fast, it will be kneecapped by US and China. Like US kneecapped Japan and China. That's the way it goes.