The best known conducting aqueous solution are that of strong acids in water best the hydronium ion (=protonated water) has the highest electrical conductivity known. The infinite dilution conductivity of of hydronium ion are compared below from the Book Chapter "Proton Transfer Reactions and Kinetics in Water" by Stillingerenter. The units are cm$^2$/ohm equivalents. As you can see, the best conducting ions in water are the hydronium ion and the hydroxide ion. The "rest" of the ions are nowhere close.

$$ \begin{array}{rllll} \hline t\left({ }^{\circ} \mathrm{C}\right) & \lambda_{\mathrm{H}^{+}}^{\circ} & \lambda_{\mathrm{OH}^{-}} & \lambda_{\mathrm{Na}^{+}}^{\circ} & \lambda_{\mathrm{Cl}^{-}}^{\circ} \\ \hline 0 & 225 & 105 & 26.5 & 41.0 \\ 5 & 250.1 & & 30.3 & 47.5 \\ 15 & 300.6 & 165.9 & 39.7 & 61.4 \\ 18 & 315 & 175.8 & 42.8 & 66.0 \\ 25 & 349.8 & 199.1 & 50.10 & 76.35 \\ 35 & 397.0 & 233.0 & 61.5 & 92.2 \\ 45 & 441.4 & 267.2 & 73.7 & 108.9 \\ 55 & 483.1 & 301.4 & 86.8 & 126.4 \\ 100 & 630 & 450 & 145 & 212 \\ \hline \end{array} $$

So, when people say good or poor aqueous electrolytes, these are all relative terms. You can choose these above values as your measuring bar. Dilute sulfuric acid in water therefore a very good conductor with respect to other salt solutions because it furnishes "protons" in water.

When it comes to the conductivity pure sulfuric acid, it will be an apple to orange comparison with its aqueous solution. There is no water (or very little), small amount of hydronium ions. The current carrying ions are now different. Look at the conductance (reciprocal of ohms, the old paper labels the y axis as conductivity) as a function of sulfuric acid concentration, it follows a very non-linear behavior and its resistance is relative high as compared to aqueous solution.

Thus the Wikipedia claim "sulfuric acid a good conductor of electricity." is a very relative comparision. Good conductor of electricity as compared to (??). The writer is silent after that! From this graph one can easily deduce that conc. sulfuric is not a very good conductor when compared with its aqueous solutions.

(Red: Darling, Horace E. "Conductivity of sulfuric acid solutions." Journal of Chemical & Engineering Data 9.3 (1964): 421-426.)

The best known conducting aqueous solutions are that of strong acids in water because the hydronium ion (=protonated water) has the highest electrical conductivity known today. The infinite dilution conductivity of of hydronium ion are compared below from the Book Chapter "Proton Transfer Reactions and Kinetics in Water" by Stillingerenter. The units are cm$^2$/ohm equivalents. As you can see, the best conducting ions in water are the hydronium ion and the hydroxide ion. The "rest" of the ions are nowhere close.

$$ \begin{array}{rllll} \hline t\left({ }^{\circ} \mathrm{C}\right) & \lambda_{\mathrm{H}^{+}}^{\circ} & \lambda_{\mathrm{OH}^{-}} & \lambda_{\mathrm{Na}^{+}}^{\circ} & \lambda_{\mathrm{Cl}^{-}}^{\circ} \\ \hline 0 & 225 & 105 & 26.5 & 41.0 \\ 5 & 250.1 & & 30.3 & 47.5 \\ 15 & 300.6 & 165.9 & 39.7 & 61.4 \\ 18 & 315 & 175.8 & 42.8 & 66.0 \\ 25 & 349.8 & 199.1 & 50.10 & 76.35 \\ 35 & 397.0 & 233.0 & 61.5 & 92.2 \\ 45 & 441.4 & 267.2 & 73.7 & 108.9 \\ 55 & 483.1 & 301.4 & 86.8 & 126.4 \\ 100 & 630 & 450 & 145 & 212 \\ \hline \end{array} $$

So, when people say good or poor aqueous electrolytes, these are all relative terms. You can choose these above values as your measuring bar. Dilute sulfuric acid in water therefore a very good conductor with respect to other salt solutions because it furnishes "protons" in water.

When it comes to the conductivity pure sulfuric acid, it will be an apple to orange comparison with its aqueous solution. There is no water (or very little), small amount of hydronium ions. The current carrying ions are now different. Look at the conductance (reciprocal of ohms, the old paper labels the y axis as conductivity) as a function of sulfuric acid concentration, it follows a very non-linear behavior and its resistance is relative high as compared to aqueous solution.

Thus the Wikipedia claim "sulfuric acid a good conductor of electricity." is a very relative comparision. Good conductor of electricity as compared to (??). The writer is silent after that! From this graph one can easily deduce that conc. sulfuric is not a very good conductor when compared with its aqueous solutions.

(Ref: Darling, Horace E. "Conductivity of sulfuric acid solutions." Journal of Chemical & Engineering Data 9.3 (1964): 421-426.)