Can large concentrations of a weak base act as a strong acid?

Can large concentrations of a weak base act as a strong acid?  Wikipedia (good source lol) states that "at high concentrations, HF molecules undergo homoassociation to form polyatomic ions (such as bifluoride, HF−2) and protons, thus greatly increasing the acidity..."
Can someone confirm this trend?  I was looking at the titration curve of a aqueous solution of HF titrated by NaOH [Kahn Academy Video Acids and Bases: Half Equivalence Point (https://www.khanacademy.org/science/chemistry/acids-and-bases/v/half-equivalence-point)]
Flouride is a weak base but it is said to increase the basicity of the solution.  HI, HBr, and HCl are all strong acids and hence weak conjugate bases.  I don't understand completely why Flouride shifts the equivalence point of the titration but chloride, bromide, and iodide do not.