I think the main indicator of altcoin value mirrors its value to people. The options and opportunities it provides. The problems it solves. Inflationary vs deflationary assets and currencies. Circulating supply. And similar facets which separate inflation protected assets from ones that are susceptible to hyperinflation and devaluation. These variables are certainly priced in. But emphasis and price projections based on these price points is discouraged. For the same reasons bitcoin being an inflation protected asset is seldom acknowledged. Even in the face of ever increasing fiat printing.
Aside from the fundamental market mechanics. Circumstances revolving around politics and world affairs definitely matter. There is a human condition element working in conjunction with metrics and statistics to determine how much an asset is worth. We can easily solve for the statistical elements. Identifying narratives and talking points which also factor into price valuation, is a little more difficult. And as relevant.