> Technology continues to advance, exponentially

Why should we believe it will continue to advance exponentially? And even if it does, we many find none of the hypotheticals pans out - perhaps we advance exponentially and there is nothing feasible to reach even 0.01c

Yeah it's always quite naïve to say technology will be always exponential. We only had like a few thousand years - if it's logarithmic we wouldn't know it for the next 10000 years.