I don’t know. It depends on the $5K tonearm. My tonearm is $6700. I’m sure I could get more out of the Lyra with a $20K tonearm, but I assure you I am getting my money’s worth with the one I have. It's the real deal.
Like I said, it’s about balance, but generalizing on cost alone isn’t useful to me. I agree with you putting a $15k cartridge on a $1K arm isn’t optimal and poor use of funds, but that’s more extreme and not something I would consider a balanced system.
On the other end of it I see people putting $1K MM cartridges on $30K Linn LP12 Klimax turntables with $800 phono-stages and I just don’t get that.