I understand what you're saying, but arguably there ARE temperature records going back hundreds of millions of years. Ice cores etc. And THOSE can be scientifically determined within some error, but certainly indicative for warm/hot periods and ice eras (not ages) lasting millions of years.
In contrast, what will happen in the future, be it 10 years, 100 years or 100,000 years cannot be measured or studied by default, and is therefore unscientific. Computer models are not science.
What I like about it is that we know from written accounts, not temperature readings, but every day life changes based on climate change. Things like during the Medieval Warm Periods people would tie their boats to the Pevensey Castle in the UK when the tide was in. Now, Pevensey Castle is a mile away from the shore (suggesting that the Medieval Warm Period rose temps enough to raise sea levels enough to bring the water more inland than it is today during the Modern Warm Period).
I'm interested in other proxy measurements showing what temps may have been like tens of thousands of years ago or millions of years ago. But not as much as I'm interested in proxy measurements from the past few thousand years, in which we can see how they match up to written history (pardon the redundancy). Things like the many famines in the Bible either during the cooling period before the Minoan warm period, or the cooling period after that (which corresponds to the Era of Kings). But only one I can think of during the Era of Judges (which corresponds to the Minoan Warm Period). That suggests that crop yields were better during the Minoan Warming Period than during the surrounding cooling periods. Things like that tell us to be happy, not sad that we live in the Modern Warm Period.