sure, new members and more visitors doesn't create instantly better Steem price.

new members means also Steem is more popular, and some of the people joins could potentially be an investor. couldn't she/he?

the correlation steem price / steem platform popularity is indirect, but there is.

some of the new member can invest and buy some steem.

new members doesn't mean lower reward pool as long as the new member doesn't post anything.

actually it could be quite the opposite, new members, most of them investors, they just buy Steem and hold it. Price Soars.