I'm not sure if the use of "on the ground" here is correct. Could somebody check it for me please?

Thanks for your help.

We say something nice, yet the implementation on the ground is completely different.
I would not use the phrase on the ground in that case. But then I don't use the phrase at all unless it's literal: I accidentally dropped my wallet on the ground. Journalists have been using that expression in the past few years -- often, but not exclusively -- to mean on the battlefield.
What do you mean?
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I mean that what is being stated is different from what is being done in practice.
 CalifJim's reply was promoted to an answer.
My take:

we say so many nice things, but at the end of the day everything remains on paper nothing materalised in reality
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