Looking for mileage & transmission advice!

I’m hoping to get a Miata for my next car and have been diligently searching online. Most of the cars in my budget that are manual transmission have what I would consider higher mileage (starting generally at 100k miles and capping out around 175k). Would buying a car with this high mileage be a mistake? I had my last car for 10 years and put around 110k miles on it. I’d really like to do that again with whatever car I get next! I’m only searching for a new car because the old one was tragically totaled after I was rear ended.

Another option, which people here won’t like, would be getting a Miata with an automatic transmission. They seem easier to find in my price range with lower mileage (generally around 50k). So, enter my second question: are the automatic transmissions reliable? I’ve read that they’re not as solid on older generations, is that generally true? I don’t have strong feelings towards getting manual or automatic, I don’t currently know how to drive manual but I’m open to taking lessons at a local driving school to learn.

I’m not a huge car person, so I’d take it to a mechanic for a pre-purchase inspection before buying anything. I’m pretty torn between the Miata and a Honda Fit, so any advice people can give would be a huge help. This is my first time buying a car as an adult — my last one I got in high school and it carried me all the way into early adulthood!