joseph
Because for better or for worse Yidishkeit is not as monolithic as you’d like it to be.
and in spite of the full scare war being waged against it there are Rabbanim who hold there is no melacha involved (R’ Oelbaum, and R” chaim shpira among others) Or that it is muttar for Cholim (R’ Nebenzal, R’ Harfanes, R’ Neuwirth) among others.
That said I have no idea why it would be allowed (generally). The safek aspect seems like a joke to me. In order for the safek to have any validity, at some point I’d expect it not to work.
In other words say it becomes popular and say, 200,000 people install 4 of them in their homes, they flip it on/off an average of 4 times over Shabbos for 55 shabbosos/ Yomim tovim over the next 2 decades. That is 2,200,000,000 uses for at least one of them the switch should take awhile to turn on/off ie. months or at the least days. I’m curious if the inventor would say this is the case. Somehow i doubt it