It was never taken seriously as an explanation of the origin of life. Without the mechanism of natural selection the notion that mere random agencies could assemble anything complex from basic, naturally occurring materials was too absurd.
However, the excitement generated by the possibility science could explain away God commanded an enormous amount of attention and effort. In the days of primitive microscopes when "animalcules," or seeming little drops of green jelly, were seen alive, could swim, seek the lighter side of their containers and so on, some people convinced themselves, if not many others, that God would be completely explained away soon. The intention at first was not to say that complex things might be assembled randomly, rather the issue was just how complex life was.
As time went on and microscope technology improved, the complexity of life was revealed. The drop of green jelly was no simple thing at all. Rather than accept defeat, the proponents of random assembly shifted their focus. They argued that given enough time, with all the possibilities that had begun to imply to them, even very complex things might arise unaided. The ridiculousness of the approach went over the heads of quite many for quite some time. Even today young people can be found on the internet apparently unimpressed by the several arguments against tornadoes building cars in junkyards for example. Creating a living thing can't take a long period of time. If, of the well over ten thousand details required at once, only one thousand are arranged, they'll not survive centuries waiting for the other nine thousand.
The pile of questions outgrew the pile of answers several times over. With our modern understanding of the complexity of life, its random assembly appears literally impossible.
Uneducated and unscientific people have not received the memo despite its being in preparation over eighty years now. They like to believe God has been explained away. Even quite faithful people like to believe that miracles are not likely or are perhaps even impossible.
Obvious indeed as it is that spirits do not intervene much, if at all, in most people's daily lives or in the universe that can be seen, the scientific fact remains that something did intervene on a once molten but cooled planet to create life in the first place.
Those whose professions do not regularly address these issues or are otherwise without scientific training, please note two things.
First, there is no random agency in the inanimate universe. Especially after Newton's Universal Gravitation Law swept away so many spirits and angels of folk wisdom, there is no repeatable, verifiable test widely available to prove any "random" event in the sense of a violation of the known laws of physics has ever occurred at all. That means no amount of time will cover "all possibilities," rather all actions are merely exacting reactions. The agencies of apparent randomness have very limited possibilities that merely repeat simple patterns, however virtually complex snowflakes and smoke swirls appear.
Second, even if such an agency could be found, several serious problems remain.
It would still be inadequate to assemble life, not only because it must have operated without natural selection, but because it must have operated in a very short time.
It would have to be truly "random" in the sense of covering "all possibilities." That means a highly disordered universe where all the spirits and angels of mere folk wisdom, not just the highly ordered interventions recognized by established religions, would be loosed again on the world.