Yes, it's "line goes up", but more in the P/E ratio sense, where the price of the stock doesn't reflect the true value of the company, however outside of tech you can usually reason that there's either dividends being paid, or the stock has a base value because if a company performs, and the stock price is low enough, it's worth for another entity to buy it out and take control of it. This gives a stock some real value, and company performance has real impact on the price of the stock. In the case of tech comapnies, it's often no dividends, and the owner has 51%, so the stock gives no share of the profits, and no voting power.
And no its not just tech