I recall the original Windows 95 release shipping with TCP/IP but the protocol having to be manually added in the Network CPL: https://eml.berkeley.edu/wp/win95/isp.html
[1] we had one T1 for internet and one T1 PRI for the modem pool, and outsourced to MegaPath for out of area dialup, and then shunted all the customers to that when the PRI stopped working