> 10W constant over 10 years would cost me 275 euro.

€2.30 per month. Which is almost nothing.

> Over 20years it will cost me ~2800 euro in today's prices.

That is €11 a month over 20 years. So the extra 10 watts is still next to nothing even taking into account your exaggerated time frames, which I am dubious as to whether this is real.

I am certainly not going to worry about €11 a month.