Is there actually a difference?

Well designed tube amps can, and often do, display astonishing detail and generally more actual tonal accuracy (harmonic content is what music is) than most SS amps can hope for. No contest.

Usually tube has good presence but loss of fine detail. Solid state sounds more tight but very detailed.

I find that tubes generally have more detail than solid state, in particular when it comes to low level detail. Its the low level detail that is the argument for tubes. Solid state by contrast is brighter (due to higher ordered harmonic distortion), and often people mistake that for detail.

Yes I can.

The short explanation is that tubes generally are more linear. Semiconductors have a significant non-linear input capacitance which as any solid state designer knows can be tricky to deal with (in fact radios are tuned by the use of varactor diodes, which take advantage of this capacitance), and often requires the application of loop negative feedback to correct the non-linearities that result.
In a nutshell, the more linear the circuit, the better it is at low level detail. It is true that

The same phenomenon that give rise to various orders of harmonic distortion exist with both tubes and transistors.

But it is also true that tubes have less of that phenomena than transistors, which is why the odd ordered harmonics to which you refer are at a much lower level in all tube circuits. That is the basis of the tubes/transistor debate, since that lack of higher ordered harmonics is why tubes sound smoother. It really is too bad that Sony sat on the SITs, if you will pardon the expression :)  They really did offer the solid state replacement for a tube!

I tried to post the First Watt paper on Sony’s SIT designs.  Didn’t know Pass made a VFET AMP based on those designs.  Why doesn’t someone else use this approach??