I could get along very nicely with a .30/06 to the exclusion of any other cartridge. Loaded with a heavy round nosed soft point it will flatten the largest most truculent game in North America. With mid-weight bullets it shoots flat enough to take deer, caribou, seals, wolves, antelope, or sheep under the most demanding conditions. With light weight bullets the '06 is dynamite for pest control. When loaded with cast bullets, the '06 will take small game for the pot and provides cheap plinking. On the range when loaded with match bullets the '06 might not lead the pack, but it will hold it's own in competitions where similar cartridges are appropriate, and in competition the most accurate rifle is not always the one that wins. While there are a few that qualify, the list of cartridges that are so versatile is quite small.
The problem the '06 faces is that folks these days are less interested in owning a single rifle to do a variety of chores. They want a varmint rifle, a match rifle, a deer rifle, a bigger deer rifle for moose, and a big bore for bears and such. Little wonder the '06 has fallen on hard times. The trouble is that our specialized rifles while very good for one particular application, are less useful for other duties that could be easily accomplished with a more versatile rifle. The fact is that a bolt action .30/06 with a 22" barrel and a variable low power scope, or a fixed 6X in QD mounts complimented with a good set of irons, will handle much of the shooting we need to do.
Lately there have been comments to the effect that the .30/06 is boring. How can a cartridge be boring? If you are bored with shooting, do something to reinvigorate your interest. I can understand that shooting an '06 from the bench at a 100 yard bullseye target could get old pretty quick, but does switching the '06 for a 6.5-284 change anything if you are still shooting at a bullseye target from the bench at 100 yards? The '06 is at it's best as a hunting rifle, so your off season shooting should work towards improving your marksmanship in the field. Can you shoot up to your rifle from all field positions, if so at what range? After a short run, how long does it take you to engage a 12" 200 yard target hit a moving target? Can you effectively snap shoot at close range targets. Can you knock down a steel plate at 600 yards without a sighting shot?
You can do these things with any rifle of suitable design, but unless you can do them how can you say that a rifle of any caliber is boring? I've been looking down rifle barrels for a long time, and I still consider these things a challenge, but them I'm just a mediocre shot by internet standards.