Any benefit to TDM in 2021?

[Darryl Ramm]

^^^ exactly, one of the most important things is finding a vendor and products with high quality drivers and good ongoing driver support so your interface will have a useful lifespan. Especially given Apple transitioning to new silicon… all the clunker old interfaces you mention will not make that transition. Good vendors of current interface products already have their drivers ported to Apple silicon. Even without Apple silicon changes Apple is capable of breaking compatibility frequently, requiring new driver releases. Ain’t anybody at Avid doing that for these post end-of-life products.

You are living in the past if you are trying to look for interfaces from Avid, they abandoned the consumer/prosumer interface market. I already pointed you at some great brands.

RME makes nice stuff but a Fireface 400? FireWire is old dying (arguably dead?) technology and offers no benefit over modern USB (RME is the best example of this, extracting impressive performance from USB 2 on up).