Aside from the fact that it's obsolete, you have a rural dialup phone line. ISDN required high-quality, conditioned phone lines, which you don't have.
*** Basic Rate ISDN (BRI-ISDN) @ 144Kb/s is engineered to function over traditional non conditioned cable pairs out to a line resistance of 1300 Ohms (DC), and does not require special line treatments other than no loading coils that are typical of metallic (Cable) telephone lines that exceed 18K Feet (18KFT), and as long as loop length does not exceed 40dB at 40KHz Nyquist signal.
BRI-ISDN, as are PRI-ISDN circuits, are routinely carried over fiber facilities by way of TDM fiber multiplexer equipment, and associated D type channel banks equipped with U-BR1TE channel units. A BTI-ISDN circuit will occupy up to three 64Kb/s DS0 time slots over DS1 (T1) facilities. In some cases, the associated T1 of a PRI-ISDN circuit is cared over two, and four wire HDSL equipment where no fiber terminal is available.
Is all of this going away, yes, just as telegraph circuits did in the 1980's, and the Passenger Pigeon did in 1914 ***
If you can't get DSL or cable or satellite broadband, there's no point in even dreaming about a ~50 year old technology making a rebirth.
*** A relatively true statement that applies to just about all legacy TDM services. ***