I can't say anything about travelling with family, but I see you have raised a separate topic about that anyway.

Although I live in SE Asia (moved to Borneo last year), I've not been able to see any of it due to strict lockdowns and border closures. But I believe that a car would not be necessary, and may be a hindrance if you want to do a lot of island hopping (though I am hoping to make a Borneo - Sulawesi - Bali - Java - Borneo trip in the Landcruiser I am currently restoring, if the borders open before I finish my time here...).

Continental Eurasia is a different story though. I've made many road journeys around and across just about every region of Russia, and I could not imagine doing it any other way. Those tourists I very rarely meet who use the train, stopping in various cities (and as much as I love Russia, many of the cities are of passing interest at best) and watching the wilderness roll past a window, seem to have a pretty shallow experience. It amazes me that so few people visit Russia as tourists, until I imagine being stuck without transport. Most of the good stuff - the magnificent drive up the Chuya highway through the Altai mountains, the gorgeous hinterland of Tuva, camping on remote stretches of the Baikal coast, driving on the frozen Lena River, camping on an empty beach on the Sea of Japan or simply pulling off just about any road and camping in the woods, is off the cards without your own transport. And the same is even more true for Mongolia, which is absolutely worth visiting if you're in that part of the world.

Central Asia is much the same story - no wonder people think Kazakhstan is boring when they don't have wheels to point at the Altai mountains, Dzungarsky Alatau, Mangystau etc etc. I would say only Uzbekistan might lend itself to travel by public transport, as the attractions are more urban than natural.

The only places I would say public transport works almost as well as personal transport for a traveller are densely populated places like India and I imagine SE Asia, as per your plan. Europe is probably OK without transport as in many countries you can't really wild camp and roam freely anyway... so the attractions are reduced to national parks and cities which you can reach by public transport. That's a generalisation of course.

I've done a good bit of travelling with public transport, and subsequently a lot with my own cars - I would never go back. The only other thing I would consider is a bicycle for places like China where you can't travel freely by car, or a yacht (which is looking ever more appealing with most likely many years of land border closures).

EO

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EurasiaOverland a memoir of one quarter of a million kilometres by road through all of the Former USSR, Western and Southern Asia.