Yes there is attrition, unfortunately. But if we ground them then there will be NO flying warbirds. Most types are well represented in museum collections so your argument that there will only be pictures is as I said, moot!
There are a lot of T-33s left but Canada has just retired there last active ones and they are up for sale. Those that are not bought and moved by the end of August this year will be scrapped. Those that are bought for restoration either to static or flying condition will survive ( for an unknown period of time but they will survive) those not bought will face certain destruction in the smelters.One hopes most of them will be saved. Most of the types extant today are due to a few guys who bought them to fly them. Some types have been resurrected from extinction due to the same reason. One only has to look at the Warbirds Worldwide directory book and Ogden Museum aircraft series of books to see just how many aircraft are preserved in Museums and those that are kept flyable.
Responsible ownership is the key. 98% of warbird owners are responsible but it all boils down to if I have the $ and go recover a wreck from Russia or the South Pacific and spend my time, effort and money to restore it. Then I and only I have the right to say what is done with it.