True change must happen from the bottom-up. It was not laws against slavery that ended slavery but moral outrage
I tend to disagree, at least in part
It was an outrage from the rest of humanity that made some backward countries like Mauritania finally ban slavery, but the first impulse was purely economic as I get it. Slavery ended not due to the lack of slaves but simply because slave labor was crowded out by more efficient mechanized labor which required highly skilled workers (in comparison with what slaves are generally required to know and do), which is hardly compatible with slavery. The public hostility toward slavery was mostly a side effect which emerged later (cp. industrialized Union states vs agrarian Confederate states in the period of the American Civil War)
The industrial revolution increased wealth and made it relatively less expensive to abolish slavery accelerating its decline but that was not the driver of the abolition movement.
Abolitionism
https://en.m.wikipedia.org/wiki/AbolitionismIn the late 17th century, the Roman Catholic Church, taking up a plea by Lourenco da Silva de Mendouca, officially condemned the slave trade, which was affirmed vehemently by Pope Gregory XVI in 1839. An abolitionist movement only started in the late 18th century, however, when English and American Quakers began to question the morality of slavery. James Oglethorpe was among the first to articulate the Enlightenment case against slavery, banning it in the Province of Georgia on humanist grounds, arguing against it in Parliament, and eventually encouraging his friends Granville Sharp and Hannah More to vigorously pursue the cause. Soon after his death in 1785, they joined with William Wilberforce and others in forming the Clapham Sect.[1]
I heard another interpretation
Namely, that it was actually the Black Death and its consequences that gave rise to capitalism and free hired labor. And the policy of abolitionism was only giving an official pretext for freeing hands required for industrial development. It is very similar to the process of Enclosure in England during the 18th century which created a landless working class that supplied free hands for the new industries quickly developing back then
Slaves werent just plantation worker or concubines
Through history slaves were usually made by invasion and oppression of foreign people and a part of them were highly skilled individuals
The problem with slavery is that you can capture a highly skilled slave (though this alone assumes that you are invading a highly developed country) and he will likely work for you but you can't raise skilled slaves. Invasion is not an option when you need millions of skilled hands, and still more so if you are an industrialized nation. What's the use of a slave who can't even read, for the most part?