It appears another "gigaleak" has gone down, involving Nintendo. According to sources online, it appears that Game Freak has been hacked, resulting in internal data from the company being leaked to the public. Those involved in the hacking community or those within general Pokemon related groups...
You have always been able to throw a ball at an unharmed Pokémon to capture it. Just had a very low chance of success unless it was either very low level or it was a great ball or one of the other ones they introduced later. But even back in red and blue you could always try it and it might work.