Two interesting thoughts that shake out of that:
- Hardware that used to be exotic and easy to control proliferation of has become significantly easier and cheaper to acquire; as an example, the MEMS gyros and accelerometers that are in your smartphone are $1 devices that 30-40 years ago would have been the size of a shoe box and orders of magnitude more expensive. Alternatively, you could download/develop code for a high-precision high-speed GPS receiver using an RTL-SDR or other low-cost software-defined radio for $20. For night vision/all-weather, you can get a decent resolution uncooled MWIR camera on AliExpress for about $1000; these have historically been ITAR-controlled, but when a factory in China starts pumping them out, ITAR kind of goes out the window.
- Software makes a lot of the exotic hardware less important too. For example, the terrain following system in a Tomahawk could likely be implemented on a $100 Jetson Nano and a low-cost global-shutter camera. Kalman filters, compute power, and redundant $1 sensors can compensate for crappy sensors.