TLDR is PRC has enough state capacity to produce and harness enough scientific talent to compete with global English in science, but likely not to replace it.

TLDR is PRC has enough state capacity to produce and harness enough scientific talent to compete with global English in science, but likely not to replace it. PRC academic system that heavily focuses on science is spitting out educated classes that can in aggregate rival the size (and increasingly quality) of the English tertiary network. The current STEM production rate is ~5M or OECD combined. People mocked at PRC academic paper mills a few years ago, but now PRC talent is topping science and innovation indexes (controlled for quality), that's the natural outcome of exploiting talent at PRC scale. Project trend to 2050 (past 26 years of new births already locked in) and PRC can feasibly hammer out 100M+ talent in just STEM, and most importantly, increasingly be able to retain talent without the best being brain drained. Effect going forward is that PRC is going to snowball the generation of high impact scientific research and it will increasingly be written in mandarin - PRC removed mandatory English education. PRC scientific base will likely be large enough to rival English RoW, the dynamic will be more the PRC science sphere will be less inclined to integrate with the Anglo sphere. Especially if translation tech improves. IMO the mandarin science ecosystem will be fine competing if not leading in her own bubble. If anything, the PRC might prefer the gatekeeping science behind language as a competitive advantage. Global science will splinter and mandarin science will be it's own pole. Shortcoming of India elite demographic dividend argument is, western academic institutes have limited capacity to absorb Indian talent, who let’s be frank, is replacing current cohort or PRC talent due to geopolitics which will make Indian brain drain problem worse and PRC talent retention better. English proficiency among brain drained elites will make spinning up indigenous Indian S&T at scale difficult, which India herself has a poor track record of exploiting. That can change with time obviously, but IMO there's something systemic happening with Indian diaspora doing well abroad for much longer than PRC diaspora but not meaningfully converting that into success for their birth country. Without India actually raising the ceiling for western academic ecosystem, you're looking at anglo and mandarin ecosystems competing closely. Unless anglos massively boost skill immigration, but that's politically difficult and the opposite is just as likely.