They're Turing complete. What else do you need?

There is a reason why Google has tpu8i and tpu8t

technically in order for something to be turing complete it needs infinite memory

The more (memory) you buy, the more you save!

It’s possible (likely, even) to have a chip fast enough for inference, but not fast enough or with enough memory to do meaningful training runs. Like the current DGX spark.