In 1990 corporations? Goodness, no. Most companies didn't even have a corporate email system. IBM was probably one of the few exceptions. And external network access required signatures from 3 VP's (one senior), your firstborn, and probably your left ovary/testicle--it basically just didn't happen.
Programming teams were colocated or they didn't communicate. CVS was an advanced idea. C and UNIX were those toys from academia--real programmers used mainframes and COBOL or FORTRAN. If you had a forward thinking team, they might circulate useful technical articles and ideas via inter-/intra-office memos. Otherwise, you bought a book or went down to the corporate library and borrowed a book. At IBM you could pull up old issues of the IBM Journal of Research and Development (which were gold--and still are).
A 128Kbps (yeah, that's 12 kilobytes) dedicated leased line was considered pretty fast and was pretty expensive. A 250MB SCSI drive was considered pretty big and local networking at 16Mbps (Token Ring) was godly and ferociously expensive.
I can go on and on ... but we're already well into "Back in my day, we walked uphill to school--both ways. And we counted our bits by hand." territory.
Even in universities, 1988-89-ish was just at the point where using ftp to pull a .tgz from somewhere might actually be faster than sending a physical letter through the mail and having them mail you a magtape in return. And you sent a physical letter because very few people in a university at the time had an email address that was generally accessible. For God's sake, in 1988 /etc/hosts could still enumerate in an actual file every single host on the ARPAnet.
The amount of technical change from 1990 to 1999 was ENORMOUS.