A lot of websites vary how they describe Taiwan based on whether they think you are Chinese (Chinese language or IP address geolocated to the Chinese mainland). Chinese get the story that is less likely to annoy the Chinese government, everyone else gets Taiwan listed as a country (reflecting practical reality). For website operators, it's a minefield - you can't please everyone, because in a geographic situation that someone cannot agree on there will always be someone to try to force you to change. Even if you express no fact, you can be criticised for not positively expressing the view favoured by your interlocutor.

The Chinese government and its loyal citizens are ever-vigilant for opportunities to pick an argument where they can try to bully someone to support their view of which places they should control the world; some others are similar, Israel for example.