no it will not overshadowed by a game like horizon
is this a joke assumption ?

This!!! 

In the eyes of the general public, Zelda may be forgotten under Horizon hype - if the latter has good word of mouth, and Nintendo doesn't step up their advertising game. We all know Zelda will get game of the month from every gaming site & publication - the informed audience won't forget it exists - but joe public who doesn't own either system it's on is another story.

very true

Horizon will most likely have double the sales of Zelda, so no, It's not a joke.

Lucky for me, I get to play both and I feel like Zelda will be the better overall game no doubt. I'm hoping Horizon surprises me.

You really think it will do double BotW? Sure its possible, but i highly doubt thats the most likely scenario.

And like I said in an earlier post, Horizon selling better doesnt mean it overshadowed it unless people are skipping Zelda just to get Horizon which seems rather unlikely.

The amount of attention Zelda has received up until this point makes that incredibly unlikely. Then again.. the insistence on pitting these two games together has always been strange and I don't see how the games are similar enough to be compared so often.

Maybe at the end of the day both games will be good and do well.. there's always that option.

Your title is clickbaity and you shouldn't be surprised by the response you're getting because of it.

Reading the OP, I can see the title is misleading.

However, I don't think the two games will interfere with each other on any major scale. I think most critical reviewers wont really be comparing them like that because while they both are these kind of open world games, the new IP is exactly that, new. Given the fact that Breath of the Wild is from a long series of games with a legacy behind them, people will be viewing it as a different game from the start. Some people might compare elements from them, but I think in the grand scheme they will each be in their own little corners of the gaming world.

No different console. Honestly do people think that suddenly 5million PS4 ONLY owners would jump on the Zelda bandwagon.

Nah both will do fine on their own.