Free space optics were attempted extensively in the ISP space 15, 20 years ago for FDD 1 Gbps links at short distances roof to roof in major metro areas, they're EXTREMELY vulnerable to falling over in rain/snow conditions, and path length limitations, compared to 71 to 86 GHz millimeter wave (using a 2000 MHz wide FDD channel going each way in a high/low split). I'm very skeptical.