"That same event from 1999 is still entirely doable"
For better or worse, no it's not. If you tried to have the same event today, it would be flooded with far more people than were there in 1999. Demand has gone up. Some of the mentioned changes are just to accommodate that; for instance, as more people show up, you're going to need more security because the odds of someone needing to be removed go steadily up.
Tickets are probably easier to come by these days (COVID notwithstanding), but it's probably still not "easy" to get them.
Augusta National probably still has a policy [0] that if a spectator misbehaves in some fashion, they will trace the ticket back to the person who first acquired it, and ban them from future ticket sales. This is why you don't hear people yelling "git it!" at the tee or wearing brightly colored wigs [1] during the event - they get dis-invited and escorted off the property.
[0] Mom & Dad used to go back in the 1970's, using borrowed tickets. After he retired he lost his connection for getting them. They always ate the pimento-cheese sandwiches, and loved them.
For better or worse, no it's not. If you tried to have the same event today, it would be flooded with far more people than were there in 1999. Demand has gone up. Some of the mentioned changes are just to accommodate that; for instance, as more people show up, you're going to need more security because the odds of someone needing to be removed go steadily up.