If not politics, maybe join a company like Tencent, gain status, connections, position until you have enough decision making power to control their choices in a way that would benefit entertainment industry first, and the company second. It's not about going into a certain direction, but rather working against censorious efforts in a smart way, politics or joining a company are only some ways of preventing it. It might not be Tencent, it might be Steam, or Amazon, or some production committee, because the process of attacking artistic works, always looks the same for any organization.
It always starts with activists of some kind, it might be a single person or a small group. They feel emotional distress, negative emotions, after acknowledging some fictional material, and then rationalize their position, finding excuses to attack the industry. (usually, the excuse with anime and manga is either "protecting children" or "sexualizes woman", with games it's also "creates violence"). One important thing to note is that their efforts are never motivated by the reasons related to materials itself, they either have an inner, personal problem (for example: some woman might feel that sexy anime girls create unrealistic standards of beauty they can't ever achieve, believing the problem is with works having such characters and influencing males perception of femininity, and not realizing that in reality, they have self-esteem issues, that aren't going to be fixed with the removal of anything, and that their speculation of how males perceive females isn't really how it works in reality, making their worries unnecessary) or they might have a secondary goal in mind (for example: a group of politicians in UN might want to ban drawn works with underage characters in Japan, not because they find a problem with it, but to create a public perception of them being against child abuse. Attacking an easy target that is commonly associated with child abuse by society, is a PR move, against the public fact that some of their members participated or are still participating in actual sexual abuse of minors).
Then they perform activities, join or contact the press and send letters to companies, asking for the removal of certain works, blackmailing them by the potential of staining the name of the company with a very serious allegation. They also might create petitions to the government, or convince/have in their group a politician of some kind lobbying for their cause.
Companies will follow their request because removing one thing from their offer is a better choice than risking having their company name stained, which could damage their efforts on gaining new clients in the long run. Because dramas about a game being censored usually fade away after a month, and players forget, go enjoy other games and never force those companies to take accountability, it's the best option for them, and they are willing to repeat it because it proved itself to work in the past.
If those activists succeed in removing something, they became power-hungry and spread their efforts to different companies, if not, they either abandon their efforts or wait enough time to try again, hoping that the changes in the hierarchy of company/country will increase their chances of succeeding. Often, their group grows, they also start infiltrating companies and political groups, to gain the power of directly influencing the organization decisions. This is perhaps what had happened to Patreon with their trust and safety team.
There is more to this strategy, and there are some less popular efforts that can achieve the same goal, but it's too many information, for me to cover, this is only the general overview, and I believe you can find the rest if you search hard enough. If you explore it well, you might be able to find solutions to the issue. Many people try, for example, to educate people on youtube, but because of how youtube algorithms work, their videos are usually recommended to people who already know about those things. This is why it's not only important to work hard, but also to work smart about these issues. No one, except people who are interested in anime/manga/games and the censorship of them, knows such things even happen. A friend of mine recently, really wanted to but a new PS5, being extremely hyped about it, and he changed his mind and decided to never buy anything from sony in his entire life, after a couple of months of just sending him news about their actions (he decided to buy Nintendo instead). A small victory, but a victory nonetheless, especially considering that it cost me nothing more than a couple of seconds of my time, copying and sending him the link to the story.
I know that the situation in HK isn't good at this moment, but it doesn't have to be good for you to take actions now. Whatever the future will bring is unknown either way, it might be better or it might be worse. In both scenarios, however, spending time now on learning anything that could be useful for your goals is a good decision, because you will learn a lot of things unrelated to it, that can be used in different situations. In the best-case scenario, you will learn how to achieve whatever you want to achieve effectively, in the worst-case scenario, you will have enough knowledge to overcome the obstacles, and either continue pursuing your goal, or at least have a decent life. In other words, it's not only about fighting censorship, but to use the motivation it gives you to develop yourself in general because the alternative is doing nothing, constantly feeling anxious about the thing you love being destroyed, and feeling you can't do anything about it for the rest of your life.