Not receiving Updates on Xbox Series X

there are still no confirmed things, some games are announcing that if you buy it on xbox one in series x you will receive the game update for free

I don't know if these server problems are related to the updates they do for the game.

I remember not long after I installed the game on my Xbox series x last year it received an update a day or 2 later and I started getting a server error message on my Xbox series x yet on my Xbox one x the game played fine without an error message.

I would presume that if a game is Xbox One X Enhanced, those benefits will also appear when the game is played on Xbox Series X, along with any Optimized for Xbox Series X benefits that same game might receive through future updates. I doubt seriously it
would be a step backward when played on the superior hardware.

Keep in mind the Smart Delivery feature, which will enable Xbox Live to send the best possible version of the game to Xbox Series X automatically. So that may be the Xbox One X Enhanced version, or (if the developer makes such an update possible) the Optimized
for Xbox Series X version. Given the choice, I'd want the Optimized version.

Yes that is what was said in recent news however, it is still possible that these classic titles could receive a definitive edition update for Xbox One and Series X/S

Yes, it is likely that your Xbox One will not be compatible with the new Forza Motorsport dashboard update or with game updates in general, as Microsoft is focused on the new generation of consoles, the Xbox Series X and S. The Xbox One is no longer being updated and Microsoft has already announced that it will end support for the Xbox One, but has not yet said when.

Elaboration:

Xbox One at the end of its cycle:

Microsoft is increasingly focused on the new generation of consoles (Xbox Series X and S) and, therefore, support and updates for the Xbox One are being reduced.

New dashboard update:

It is likely that the new Forza Motorsport dashboard update, or other game updates, will not be compatible with the Xbox One.

Focus on the next generation:

Microsoft has already announced that it will end support for the Xbox One, and its attention is directed to the Xbox Series X and S, the most recent generation.

System updates:

Your Xbox One may no longer be receiving system updates, or the updates you do receive are only to ensure the security of your console.