Sad to say, but it only took 7 posts in this thread for someone to start calling someone else an idiot - and that seems to be a trend on this forum.
Why don't we try to get somewhere near the original intent of the OP? He seemed to be asking about the most popular cartridges among reloaders.
I can't find any actual data on the reloading side, but I did just read an article on the rising and falling popularity of several cartridges based on sales of ammunition and rifles chambered in those cartridges. Rifle Shooter Magazine published this in July of 2020, so there may be more current information, but the observations they make do seem to reflect what's going on in the market today. Here's the link:
Top big game cartridgesHere's the reader's digest version of popularity trends, according to the article:.243 Win - holding steady. The 6mm Creedmoor has made some inroads, but the .243 Win still is king of the hill in this caliber.
25-06 - king of the 25's, but that's not saying much. The 25's as a category are sinking steadily.
6.5 Creedmoor - continues to rise in popularity, eclipsing the 25's and much of the 7mm crowd. The 6.5 PRC is making the best showing for second place in the 6.5 category, with a slew of hotshot contenders lagging behind.
270 Win - strong support for this cartridge, but a slow decline on the charts overall.
7mm Rem Mag - king of the 7mm's in popularity. 7mm-08 is sinking steadily, but will not likely disappear in the author's opinion. .280 Imp and 28 Nosler are each showing a bit of a rise, but neither comes close to the 7RM.
30-06 - no longer the king of the 30 cals - the .308 Win has been ahead of this vintage offering for quite some time. The 300 Win Mag retains a strong following among those who want more velocity with a .308 cal bullet.
Above the 30 cal cartridges, only the 350 Legend seems to be rising in the charts, and it's too soon to know if it will last. The big magnums seem to be fading steadily.
That's it - I'd still like to see what cartridges reloaders are favoring.
We know reloaders are die-hard individualists, but overall sales of dies have to at least be influenced by overall popularity.