I remember being called out for playing multiple players once.. 2 players on at the same time for about 2 seconds.. and caught. But that was in the 90s. The interenet has changed a lot since the 90s. I have several email addresses now, and not intentionally (ex. work, family, personal..). Also, having access to multiple IPs is easy now.
If you dont think the change in times is fully responsible, then you have to look at the "real" playerbase. Sorry kids, but most of the real players are in our 30s now. We have money, knowledge, and assets...
for the record tho... I don't multi. I don't have to.