A big part of how indentured servitude was replaced with chattel slavery involved things like land being provided to white former indentured servants as part of establishing a larger white property-owning class to entrench the new system of racialized slavery, so in practical terms many of the Irish indentured servants in the Americas got their reparations centuries ago.

In contrast former slaves were suppressed, subject to hyper-exploitation from new systems that aimed to recreate chattel slavery as much as possible, and terrorized with both legal and illegal violence from state and paramilitary actors, and these things have been ongoing to one extent or another for over 150 years now.

Both of those different approaches were used to reinforce the concept of whiteness and establish the cult of white supremacy as hegemonic in the US and globally. Sort of like the practice of emancipating and adopting the most loyal and skilled slaves even as arbitrary and indiscriminate terror was applied to slaves as a class in antiquity but scaled up to an almost industrial level, making the most conformist white workers into yeoman farmers whose material interests suddenly align more with other property owners while at the same time applying arbitrary and indiscriminate terror to black slaves and former slaves. Thus workers get divided, cronies get empowered, and hyper-exploitation is enabled through violence and systemic exclusion and othering.

Ireland on the other hand should get reparations from the UK because of the centuries of violence and extraction the UK has imposed upon it. But that's distinct from indentured servitude in the Americas.