My experience at the time was that it was perceived as not serious enough and lacking important features. If my memory isn't very bad, I believe as late as 2000 SQL Server still only supported AFTER triggers.
In my experience in the late 90s and early 00s, besides Oracle and Sybase, DB/2 and Informix were also regarded as good. Oracle was considered the best though.
2000 for sure had instead of triggers.. I used them :-)