My observation, there are different factions in the Thai government. The Tourism ministry always supports easy visas and more tourists and the Immigration ministry and ruling elites who are already rich and do not care very much about the economy are more anti-tourism
So the Tourism ministry will announce these things, but there is no approval--
Eventually the elites are pressured by the government economists and advisors to allow things like weed or more tourists because the GDP is falling, but the elites always demand some concession like temporary approval only