What is the chain of importance in analog system ?

It's all important. As you say different folks, different chains. Mine goes turntable, tonearm, and a tie between phonostage and cartridge. I've heard cheap carts sound amazing on great platforms, but I've never heard a high-priced cart sound good on a cheap platform.

As a 20 year professional in the high end audio industry, Dopogue is correct.

A turntable must isolate the phono cart from internal and external vibrations which will distort the output of the phono cartridge. Once a cart is isolated can you hear what the cartridge is capable of doing. So the most important step is the table.

Once you have a good table then come the arm which must drain away any extranous vibration. The arm must be frictionless so the cart can track. So the arm is next.

Then and only then can you hear the cartridge.

The better the cartridges resolution the better the phono stage so they phono stage and cartridge really are equal in their importance.

Most important unit is the Phono Stage.

By far.

Followed by
-Turntable
-Tonearm
-Cable
-Cartridge

Usually I do not like the term "chain of importance" but it is tempting nevertheless......

Based on my 3 decades in high-end analog audio:

1) the phonostage - all the more if a LOMC is used
2) a rather close 2nd: the TT
3) much more important than the individual class of each component inidvidually seen: the match of cartridge and tonearm

I see lots of folks with inexpensive arms using expensive moving coils and living with noise and hum which overwhelm my poor ears. I am running a $250 moving magnet cart with a $ 2000 turntable, a $1000 arm, $400 silver interconnects fed into a $2000 phono stage. On a quiet recording, the groove rush is inaudible and I hear no mistracking. I agree 100% with Dopogue.