The Life of a Backpacker in Asia in the 1970s (2018)
(with the disclaimer that it has been 30 months since travelling widely)It's still possible. 99% of travellers proceed along narrow planks of tourist hotspots that represent 1% of what is interesting in the world. Once it was lonely planet trails, then tripadvisor routes, now instagram pin plots. It's so easy to step off those paths, and doing so is very rewarding. Use those guides as guides as to what what not to do - at least not for long.