This is exacerbated by the fact that neither political party bothers to engage with the Asian American community. Notice that Hispanics also have lower turnout rates.
Unfortunately a lot of this has to do with the size and distribution of Asian Americans. There are over 3 times as many Hispanics in this country as there are Asians. And many of those Hispanic voters live in crucial swing states (AZ, NV, FL, etc.) plus without winning over a consistent segment of Texas Hispanics, the GOP would've lost in 2000, 2004, and 2016.
Honestly, Asian Americans aren't gonna become a targeted demographic group until states like Washington and New York come into play. This requires the GOP to abandon their southern strategy and to court upscale voters of all races. Asian Americans will become a crucial voting group in such a realignment.
I was going to respond to the rest of your post about Asian stereotypes with my own personal experience but my experience is pretty unique compared to the average American. I grew up a couple miles away from little Saigon and had a lot of Vietnamese friends growing up. My first manager was a 29 year old Vietnamese guy (though he was raised here) and I hear Vietnamese every day at work from coworkers and customers. Probably a very different environment than most Americans have experienced.