That is a good point. But all these had racist reasons at their core.
Can this be better implemented today?
With extensive supervision and scrutiny.
For example, teenagers routinely join the army, and spend time learning and training at what is essentially a boarding school. It seems to work quite well.
I'm not sure replacing racism with classism (oh, you are poor, you need to go away to school) is much better.
Extensive supervision and scrutiny? I mean, are we not doing some of this with public schools now? And if not, why not?
And seriously, we (in the US) allow lots of options for troubled kids without supervision ("work the bad out of you), we've allowed conversion therapy for LGBT+ children, have little oversight on for-profit schools and we allow folks to force their religion on their children, even if the 16- or 17-year-old doesn't believe.
I highly doubt there would be oversight.
I'd also like to point out that the Canadian schools were really, really recent, and I don't think much has changed since.
In a some cases they had racism at their core - but that's a step removed.
They thought that the parents were (for whatever reason) incapable of raising their children appropriately and that the best way to properly raise the children was away from their homes, their cultures and their problems. They may even have thought their goals were noble and justified - as most folks tend to.
I cannot see a meaningful difference between taking kids away from their parents for racial reasons, for class reasons or really any other reason.
The issue isn't necessarily why they saw them as inferior, it's that they saw them as inferior.
> For example, teenagers routinely join the army, and spend time learning and training at what is essentially a boarding school.
This choice is made by the family and the individual. This is not the same thing. A meaningful harm vector is the removal of autonomy.