If expectations of growth are already priced in, why do markets trend upward?

In the last few months i've been trying to educate myself a bit about how markets work.

I'm kind of stuck trying to make sense of the following question about index funds or market trends more in general: assuming the efficient market hypothesis broadly makes sense, expectation on future growth is priced in securities. Things don’t cost their intrinsic current value but more of an expectation on future value which should stabilize (i.e when all info is absorbed by a market). That makes all the sense in the world to me.

If so, why do markets consistently trend upwards after adjusting for currency devaluation?

For instance, the most common explanation i've read is around is: when buying into some market index, you're buying a chunk of an economy betting that i'll increase productivity, and become more valuable, and benefit from that. However, if you think of it from an EMH perspective, expectation of growth is already priced in securities, so when buying ETFs tracking sp500, you're not betting on the companies growing, you're betting that they'll grow above current expectations, cause the expected growth should be priced in.

From that angle, betting that sp500 companies are currently undervalued doesn't seem intuitively a good bet to me, or at least one that's sustainable — as in based on value growth, not some speculative scheme of the kind "it'll continue going up so long as people think it'll go up".

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Basically, i'm looking for an explanation on why these two things are compatible:

(1) future expectations of growth are priced in securities

(2) markets will predictably go up — faster than currency devaluation — in the long run sustainably (e.g. 50-100y timeframe, leaving extinction level stuff off the table)

I suspect the explanation is "something something dividents", and why companies don't need to perform above expectations for stocks to go up. But I haven't found anything that clicked.

Where does my reasoning break down? Or is something else driving markets up on the long run (besides the usual "tech improves, productivity improves, economy grows") like:- Increased money supply from central banks and debt issued by private banks overwhelmingly favors publicly traded (big) companies- More and more people get into markets (i.e. world population going up), once that stops markets stop growing.

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Thanks!

EDIT: wow thanks so much everyone! Many of your answers helped me get an intuition on why points 1 and 2 are compatible. In hindsight i should’ve phrased my question more precisely i.e. “assuming a perfectly efficient & rational market, how can 1 and 2 be compatible”, cause i was more concerned about understanding how the idealized case made sense, not so much whether EMH is true or not empirically.