I think the OP meant it metaphorically. "Basically" seems to signal this. Since metaphors are not the thing itself, there are necessarily aspects that do not fit. However, metaphors may be bad metaphors. So you may or may not have a point here. But this point should be made explicit to move the discussion forward.

Also, I suspect that the OP is not a native English speaker, because there seems to be a subtle difference between a narrow standard metaphorical use of "slave labo(u)r" in English along the lines of "work that is done by enslaved people or by people who are treated as though they are enslaved"[1] and a wider use for example in German were "Sklavenarbeit" means something like hard work under degrading conditions.[2]

[1] As Merrriam-Webster defines it at https://www.merriam-webster.com/dictionary/slave%20labor

[2] Cf. for example the lemma "sklavenarbeit" in Grimms' dictionary: "sklavenarbeit, f. arbeit, die ein sklave thun musz, die einem sklaven ziemt, harte arbeit. Campe, schlavenarbeit, lavoro, fatica da schiavo. Kramer deutsch-it. dict. 2 (1702), 562a: schlavenarbeit thun müssen, dover faticare da schiavo. ebenda; was ists für mühe und sklavenarbeit der ackerbau. Herder bei Campe." https://woerterbuchnetz.de/?sigle=DWB&lemid=S30002

I think you will find that at least in UK English, "slave labour" is used almost exclusively in the second sense [1]. The UK not having reckoned as much with its history of actual enslavement, this term is significantly less loaded than it is in the US.

[1] Oxford dictionary: " (informal) work that is very hard and very badly paid", https://www.oxfordlearnersdictionaries.com/definition/englis...

Yes, very true, nice work. Yes, not a native speaker. Middle of Europe. Actually, several hundred years ago, our ancestors were slaves here :) (probable origin of slavs, who knows)