Onaj, even in May you should have realized that there is no chance of the borders reopening anytime soon. At the time Vietnam had just emerged out of it's lockdown (a second one occurred July 25) and now we're still no closer to open borders. If you can get into Cambodia, Vietnam or Thailand, with rare exceptions it will only be by air and you'll be taken into quarantine.
I can't predict the future so won't even try, but depending on the WHO advice, who wins the US election and whatever happens behind the scenes, I think a loosening of travel restrictions could happen as early as January or February (though this appears to be rather unlikely at this point) to as late as over 1 year from now.
We also don't know what future travel will look like. The majority of countries worldwide except for a few European and American nations, require a PCR test to enter the country (or it's done at the border). How overland travel by car or motorcycle, or even by bus will look like once borders reopen remains to be seen. It could mean proof of vaccination, a PCR test or one administered at the border while you wait for up to 48 hours for the test results. Of course, the latter would be unworkable for overland travel.
Anyway, I think realistically, we're not going to be crossing any borders anytime soon.
