I hope for S 1 & 2 Remasters as well, but I think even without that we can still get our sales numbers. Since E3 of 2015, Shenmue has been getting massive exposure in all major gaming media, worldwide. Now be that positive or negative coverage, the name is still getting out there and a lot of people are gonna want to try S3 out.
With Yakuza for instance, number 3 has been the most successful entry so far. And that was a PS3 game, which had a much smaller user base at the time of Yakuza 3's release than the PS2 had at Yakuza 1 and 2's release. That's also kind of mid-story. If you haven't played 1 and 2, you won't be able to understand Yakuza 3's story to the fullest but you can still follow it and have fun with the game.
It's basically the same with S3. You'll never understand the full depth of the story and all its characters but you'll still be perfectly able to follow the main story line. You can easily sum up S1 and S2's story to make it accessible to newcomers with the cinema shorts YS Net have planned.
You play as the young Japanese martial artist Ryo who grew up in the suburbs with his father, a martial arts master who runs his own Dojo. In November of 1986, a Chinese triad boss named Lan Di breaks into the dojo and murders your father over the Dragon Mirror while accusing your father of having murdered a man in China in the past. You then start to pursue your fathers killer and find another mirror hidden at your house which the triad is also after. At the same time, Ryo starts dreaming about a country girl from China who also seems to be connected to the two mirrors. A Chinese martial arts master named Chen tells Ryo that the mirrors will resurrect an ancient Chinese monster called Chi You. Ryo fights a local Hell's Angels ripoff gang which is working for Lan Di and learns that Lan Di went to Hong Kong. Ryo follows him to Hong Kong and learns that a Chinese martial artist named Zhu, who used to be friends with Ryo's father is being held captive by a local gang which is also working for Lan Di. He teams up with a rival gang leader, Ren, to rescue Zhu. All the while making friends with loads of other martial artists in Yokosuka and Hong Kong and fighting lots of battles to become an ever stronger fighter. Zhu then tells Ryo and Ren the mirrors form a treasure map and says that Lan Di probably went off to mainland China, to the Guilin region, were the raw material of the mirrors can be found. Ryo gets on the next boat to the Guilin region where he runs into the girl he had seen in his dreams. And bang. There you are, in 1987's China and S3 starts at Shenhua's house.
You see, it took me like 15 lines to sum up the basic story of S1 and S2. Put that into a 5 to 10 minute video clip (nobody's gonna watch anything longer than 10 minutes) and it will be perfectly possible for anyone new to Shenmue to play S3.
Of course I'm still hoping for the Remasters but I think it is still feasible without.