What people are calling an "algorithm" is really a heuristic.
In the public discourse over "algorithms", the definition seems to be "something that maximizes your (time on site|outrage|clicking)" and not the real definition
In mathematics and computer science, an algorithm (/ˈælɡərɪðəm/ ⓘ) is a
finite sequence of mathematically rigorous instructions, typically used
to solve a class of specific problems or to perform a computation. [1]
By that definition any well-defined process that creates your feed (sorting chronologically, alphabetically) is an "algorithm"; in the machine learning age it is easy to make an algorithm that selects for anything at all, except for the capital-T Truth.
[1] https://en.wikipedia.org/wiki/Algorithm