Heck, a lot of Vietnamese prefer studying and working abroad in Thailand because salaries and development is higher than in VN and only the elite can afford to send their kids to VinUni or RMIT Saigon.
The original premise that Thailand is cheaper than India is definitely wrong, we both can probably agree on that.
I think the issue was Google Search's summarization algorithm parsed the wrong sentence in a non-verified website (I did the same search you did and recreated your issue).
Also, the same thing holds for China as well. BKK =/= Thailand and Shanghai/Beijing/Tianjin =/= China as well. Not to mitigate the massive amount of development that China has seen the past 20 years, but Thailand's subregional development (measured via HDI) is very even - the poorest region (Isan) has a HDI of around 0.781 and the richest (BKK the prefecture, not the city) is around 0.839 in 2021. Compared to China outside of Tier 1 cities it's a significant difference (and on a separate note Ik Chinese policymakers have been looking into Thailand's anti-poverty policies to replicate them in Shaanxi)
Thailand back slided during the last decade because of political instability. Having a military coup every couple of years isn't great for business. Although I agree that .68 is too low for Thailand from personal experience. It feels like Thailand should still be above China, but I'm not confident in making that call without seeing the numbers crunched (so I'm willing to accept your numbers more than the ones I found via a quick Google search).
Generally speaking, the median Thai person does tend to have a better life than the median Chinese person, simply because poverty eradication has been a pretty significant plank of both the Junta and the elected politicans, plus the massive amount of FDI coming in from SK+Japan after the whole 2013-2017 trade war.
But then again, comparing a Billion+ country that gives significant administrative autonomy to provinces with a unitary country with a population comparable of Zhejiang might be unfair. At least on a developmental and economic level, Thailand would be comparable to Jiangsu or Zhejiang.