Dear Downunder: I can't for sure answer your question. Many people here already give you some differents answers and all of them ( one way or the other ) could be right.
As you know I'm already in a tonearm design where I'm learning how complex is a tonearm design/build.
Cero tracking error is a desired goal in any tonearm design and in a pivoted one the theory tell us that a larger arm has lower tracking error, good but this tonearm atribute/subject alone means really very little about the performance tonearm, there are other factors/goals that could be more important to the whole tonearm performance: bearing, build material, effective mass, static/dynamic balance, isolation, internal wire, etc, etc.
My experiences with a lot of tonearms ( any size you want , including linear trackers. ) and with a lot of different cartridges tell me that that lower tracking error is not so critical ( because is very small anyway. ) like you can think about.
Now, that person that post here that through a long SME his cartridge sound performance level goes up means that that cartridge is better " served "/match with that tonearm but not because is a long type tonearm, this new tonearm is a different tonearm ( not only in its internal wire ) than the one he normally use it. So we can't say that a long type tonearms sounds better or have some kind of signature sound performance advantage because it does not have it perse.
Any well designed tonearm ( short or long ) can/could perform in a great way with the right cartridge.
The same for the people that thinks that the linear tracking tonearms are better because has cero tracking distortion and mimic how the LP was cut/recording. IMHO any one of these people that favor the linear tracking tonearms over the pivoted ones happen that any one of them never had/have the opportunity to hear a pivoted tonearm with its right matched cartridge, that's all. Yes I know that them already heard a lot of pivot tonearm but maybe never the right tonearm/cartridge combination!!!!!
All those theoretical advantages about tonearm tracking error in long tonearms and in linear traking ones are really too relative not only for what I already posted here but because all the recording LP process is not a perfect one and not a perfect one the cartridge/tonearm set up so that theoretical advantage are far from be a real advantage and more important that that theoretical advantage was/is the main cause of a better quality sound performance.
There are many subjects to discuss about and maybe in other time we can/could do it, it will be very learning for all of us.
Regards and enjoy the music.
Raul.