Using Orbi RBS750 satellite with RBR850 router

I have an Orbi RBK 853 which consists of 1 RBR 850 router and 2 RBS 850 satellites.  I need a third satellite and none of the RBS 850 are currently available.  I bought an RBS 750 satellite and it works well with the RBR 850.  All satellites have wired backhaul.

By mixing two different WiFi6 hardware series, have I harmed the system in any way?  I have read that, when older Orbi WiFi5 hardware series are mixed, the resulting system slows down to the slowest hardware.  I suppose the chain is only as strong as the weakest link.  I’m not noticing any system performance degradation but, after spending nearly $1000 on the RBK 853, I don’t want to hamper performance by adding an RBS 750 just because it was available and the RBS 850 was not.