I don't know if GOG takes suggestions, but I would love to see some of those old manager games preserved.

Suggestions can be made here: https://support.gog.com/hc/en-us/requests/new?product=gog&form=other

Apart from that, there is the community wishlist: https://www.gog.com/wishlist/games#search=football%20manager

Now, when it comes to football, there may be (a lot of) licenses involved.
And licences are among the top three reasons as to why old games don't get re-released.

So, maybe don't hold your breath.

You could make your own football manager. For example, here is a ZX Spectrum BASIC Football Manager. They're a good excuse for a programming exercise, because they're lousy with numbers.

Or if BASIC is a bit too complicated for you, there's always a spreadsheet program of your choosing.

That sort of game would be among the top examples in the definition of licensing hell. Expired licenses for players, clubs, associations, logos, you name it, some defunct, some having changed hands, then different licenses for the game title, engine and possibly other elements as well held by different devs and/or publishers, some defunct, some acquired, with or without portfolios, some having changed hands multiple times...

Championship Manager 01/02 was made free(ware) by publisher Eidos and is free to download.

Nice to know, played that game to hell and back. My older brother still play this types of games ever since.