Sadly it just the way it goes. The remasters usually become the new main ones and the originals are left behind. Which is a pity.
The 2001 Madonna remasters became the standard editions for those three first albums, and mastering is very different from the originals.
"True Blue" is even worse cause with the 35th digital edition it got an even louder worse mastering and every digital edition of the album was updated with that one.
I'm not against remasters per se, but always keeping the originals, especially on streaming. I don't like the rewriting history part of that when the just upload the new files and delete the originals.
As fas as I know, only Qobuz now has the first 4 albums in their original form/mastering:
https://www.qobuz.com/es-es/album/madonna-madonna/0093624951131
https://www.qobuz.com/es-es/album/like-a-virgin-hi-res-version-madonna/0093624951117
https://www.qobuz.com/es-es/album/true-blue-hi-res-version-madonna/0093624951124
https://www.qobuz.com/es-es/album/whos-that-girl-hi-res-version-madonna/0093624951148
But wow at those prices.