I think this back and forth between Chinese and Indians started only a few years ago when some Chinese who visited India started to look at their news, comments and social media. They were shocked by some Indian's arrogant views of themselves and of China, so they shared that finding with other Chinese via social media. This is surprising to Chinese as from their perspective, India is far behind in terms of industry, infrastructure, organization and STEM education. This is not coming from Chinese who haven't visited India but the ones who went there and saw for themselves. As a reaction you will see many Chinese in recent years making fun of India, its just a reaction to their perceived arrogance from Indian media/politicians, now it snowballed. Its a very recent phenomenon, if you look at older comments you will see quite positive comments of Indian progress by Chinese as words of encouragement.
https://defence.pk/pdf/threads/in-5-years-people-forget-about-shanghai-and-talk-mumbai.26534/
"India 2030" video (honestly its degrading and cringe worthy, shouldn't be posted)
I understand where some Indians are coming from with them thinking India is better or should be better than China. I have talked to many older educated Indians in the west. Other than the usual talking points, they don't understand or haven't come to terms with why China should be ahead of India since India was left with better infrastructure and a British educated elite post independence. Don't want to explain the reasons for China's rise here but I understand its hard to swallow pride when a country that was poorer, worse infrastructure, perceived as inferior by the Indian elite is doing better technologically, industrially, and economically for a prolonged period. Most Indians in the west are fine people including educated ones coming from India that I've met.
IMO is not so much that India is doing bad because its actually above average in terms of growth and trying to engage in large scientific projects, its just the sad reality that its competitor/rival is China who is much better at organisation, technology, and industrialisation than any other developing nation. Both nations rising at approximately the same time with similar global ambitions thus dictating competition. Individuals can get along but nations are interest groups beyond the individual.
Regarding industrial copying, the people who are in charge of industry are engineers and physicists who think in the framework of physics, which means they emphasise having the knowledge and having the industrial base, all others considerations like design and marketing are secondary and afterthoughts. Unless China is going to relive 300 years of British industrialisation it better skip steps much like the Germans, Americans, and Japanese who were all known for copying in order to catch up to the industrialised world. Most countries can't even learn and replicate what is freely available on the markets. In recent years there are many innovative and internationally successful products from China, it would be ignorant to say otherwise but Chinese just have high standards for themselves. Chinese understands problems within China and wants to improve upon the economy of China but they feel funny when some Indians say they are better than China or make fun of China.
Needlessly bashing anther country is counter productive, its better to celebrate successes of science and technology for mankind. Maybe its my personal value but I think anybody/organisation contributing to furthering mankind is a positive force and anybody/organisation taking progress away should learn from the positive force or not be given fuel or should be eliminated from civilisation. Those in the middle should be happy there are people hard at work making your lives better.
TLDR; Chinese tend to make fun of people they perceive as arrogant and look up to hardworking countries/individuals they can learn from.