Muley,
Contrary to what you may believe, its not always about you and if you want to resort to insults we can take this up another way.

The 243 and 30-30 have more in common than you may think. Both Nosler Partitions (100gr vs 170gr) have a not too different sectional density. 240ish (243) vs 250ish (30-30).....im assuming you understand why a high SD is beneficial for penetration.

Muzzle energy is not dramatically different. At least its not like comparing them to a magnum class chambering. 243 100gr...roughly 2000fpe+...30-30 170gr almost 1900fpe.

Light recoil for those sensitive to recoil. Quite often this is an advantage for some hunters vs using a magnum or even a good old 45/70.

At 100 yards though thing start to change quite a bit. The higher BC of the 243 100gr Partition starts to show some value in retained energy/velocity and by 200 yards the 243 still has about the same energy as a 30-30 has retained at 100 yards...roughly 1300+fpe.

Neither one is very impressive in TKO factor but i would give the edge to the 170gr Partitions. The velocity edge certainly goes to the 243 and arguably the more abundant/accurate platforms...a bolt action. Your average 30-30 lever gun is not likely to win that accuracy contest too often and bolt action 30-30s are not exactly common by comparison.

Most people know speed kills very well and shot placement is king. The Euro block has been using the 6.5x55 Swede for many years on game quite a bit larger than our deer including moose. Those long 139-140gr 6.5 bullets have done quite well when the bullet hits its mark. Yet the muzzle energy is not dramatically better than a 100gr 243.

Did you have any facts to add or just an opinion on why a 30-30 is ok but a 243 is not? As i said, i would not recommend either but its certainly possible.