If Star Wars fans could put enough pressure on Disney to bring back The Clone Wars for a final season, then I'm sure Pokemon fans can put enough pressure on GameFreak to actually make some changes (for future games if not for SS)

After The Force Awakens and The Last Jedi, an alleged "vocal minority of fans" boycotted the Han Solo movie, which caused it to bomb and grossly underperform in the box office. A few months later they announced that they'd begun production on The Clone Wars final season

For those not interested in Star Wars, The Clone Wars is a CG cartoon created by George Lucas and his successor, Dave Filoni, to bridge the gap between Episode 2 and 3. It was cancelled after the Disney buyout, and the final season was left on the cutting room floor (back in 2014). Fan backlash to the direction Disney was taking with the Star Wars IP prompted them to bring something back that fans actually wanted (the final season of the show).

If enough people actually refrain from buying Sword and Shield, it could send a big enough message to GameFreak to actually put some effort into future games.