I purchased the Standard Edition at launch. I knew I would want the DLCs at a later date and believed that the DLC would be bundled and discounted at a later date. Was this expectation unreasonable? No, absolutely not. Historically with Civ and other games this would be normal practice.
civ1 had no additional content at all and
civ2 had 2 CDs (maps, scenario pack etc.), but no expansion in the sense of a
systematic ongoing development planned completely in the beginning (eg. civ3 had ResearchLab not until the 1st expansion etc. IIRC) ...
civ3 &
civ4 had (several months after the 1st expansion release) the base game & the 1st expansion bundled & discounted ("Gold Edition"). Also the same with the base game & the 1st expansion & the 2nd expansion bundled & discounted ("Complete Edition").
civ5 introduced additional to the 1st expansion & the 2nd expansion
also DLC packages.
But the DLCs were not bundled & discounted.
civ5 followed exactly the old civ3 & civ4 pattern: base game & the 1st expansion & all DLCs up to date bundled & discounted ("Gold Edition") - the same with the base game & the 1st expansion & the 2nd expansion & all DLCs up to date bundled & discounted ("Complete Edition").
So "
Was this expectation unreasonable?" No, but it wasn't reasonable either - maybe you describe alternative 'history & normal practice'.
My expectation is simply that civ6 follows the civ5 scheme (well, except the different delay between base game & 1st expansion for obvious reasons).
For reference:
Here you can see the release dates and prices of the german
civ5 versions, packages & bundles.