Is there any Chinese brand as good as Shimano? Or is it just its reputation? For me, who is not into competitive cycling, I would ask for a MIC brand if there is that alternative.
Tough question. Shimano has many levels. Dura-Ace is the best and I don't think Chinese companies have an answer yet but we are very close, sometimes neck and neck with Ultegra, the second best and most frequently used groupset by semi-pros. (Ultegra is also what was used to win the junior champs I mentioned above.) We have several options that are lighter while performing on par or better with Shimano's 3rd tier groupset called 105, or the people's groupset as it's known for being the favorite of all cyclists that are not good enough to be competitive but have a refined taste for excellent bikes.
Shimano is the most vaunted company in cycling components. Eversince Shimano invented index shifting (shifters and brakes in one handpiece as opposed to shifters on the downtube and brake levers on the handlebars), they have left Campagnolo in the dust and never looked back. SRAM is an American challenger and 10-15 years ago, the cycling world was made of Shimano, Campagnolo and SRAM as your only 3 choices for modern groupsets. Shimano was the smoothest; SRAM was the lightest, and Campagnolo was for snobs.
Around 10-15 years ago, an incident ocurred at SRAM that saw several Chinese engineers leave. Those engineers founded 2 Chinese companies for components. Those are Sensah, and LTWOO, the latter of which clearly copied Campagnolo. This was the age of cable shifting and those 2 groupsets were known to be pretty good, very good for the money, but just lacking refinement compared to the big 3.
Since then, the age of electronic shifting began and electronics is where China truly excels. Sensah has done ok, but LTWOO has become the frontrunner for electronic hydraulic disc groupsets. They are truly a hair away from Shimano's mid-high tier smoothness and you would never know. Others include Wheeltop, which makes an app-controlled groupset that can be set up to anything from 7-13 speed, and Magene. Magene makes a groupset that is very similar to Shimano (usable in China only due to the need to download an app that can only accept registration from Chinese phone numbers) but recently, they goofed. A design flaw led a Chinese cyclist to lose all braking power and ending up hospitalized from an uncontrolled descent. Word is, the company was unapologetic and tried to blame it on the user until many places and people experimented proving that it was a design flaw with their hydraulic fluid reservoirs being too small.
All in all, I recommend you go with LTWOO. Their electronic groupsets are superb (~$500-600) and only a real pro would notice any slight difference between that and Shimano. You can also buy their older cable groupsets (~$200) and save a lot of money that way. They work just fine, don't need charging, but are not bling bling and not as refined as the electronic stuff.
I strongly recommend Trace velo for keeping up with Chinese cycling tech, which are extremely plentiful from bikes to groupsets to simple single components like cassettes, 3D printed saddles, carbon derailleur cages, cranksets, etc... that can save a lot of weight (pay attention to Trace's reviews as some are trash and some are gold). This channel is run by a Brit named Luke who buys everything on Aliexpress and reviews them, from chains that are garbage and last 6 rides to total Chinese bike builds that he deems are the best value in the world by far.