Funnily now with with the advent of GPS+RTK lawnmower robots, fancy AI is not even needed anymore. They follow a very exact, pre-determined patterns and paths, and do a great job.
Didn't work as well as I'd hoped back in those days though, as you could lose carrier lock if you got too close to trees (or indeed buildings), and our target market was golf courses which tend to have a lot of trees. And in those days a dual-frequency RTK+IMU setup was $20k or more, which is expensive for a lawnmower.
No tool is perfect for every job. That said, the positioning of the RTK unit is crucial. Possibly look for a mower which can work with multiple RTK units, or reposition your existing one for better coverage.
I find that even though signals get significantly weaker under trees, mine still works wonderfully in a complex large garden scenario. It will depend on your exact unit/model, as well as their firmware and how it chooses to deal with these scenarios.
