Long considered to be the pinnacle of PC-based racing simulation, iRacing is clearly noticing that the rest of the industry is riding firmly in their draft, and possibly poised to take the lead.
From its inception, iRacing has had a very narrow focus on competition: online racing only. Sure, you could hot-lap alone all you wanted, but if you wanted to practice against other drivers, you had to join an online practice. While this provided a true-ish representation of the competition you would face in a real race with other drivers and cars on the track, it did not necessarily prepare you for the extreme differences between practicing and racing. Most obviously, the cars are spread all over the track during practice sessions, and almost no one will fight very hard to protect a position. In practice, you typically aren't driving at full speed surrounded by a gaggle of other drivers that view you either as an obstruction or an opponent. In a nutshell, there is a great deal of difference in the stress levels between practice and racing. The only way to truly practice for racing is to race, but iRacing is extremely unforgiving of racing mistakes.
So, yes. iRacing provided access to the what are ostensibly the best possible opponents: humans that have skin in the game. That said, it is highly inconvenient. Popular classes have races scheduled every half hour or so, but the higher you climb in the tech tree, the rarer the races are. Many of the higher classes schedule a race no more frequently than every two hours. That doesn't sound like that big of a deal, but consider waiting for your two hour racing appointment and getting knocked out in the first lap of the race by some knuckle-headed rookie that powered through the experience-gaining race classes without taking the time to really learn the craft. That is not uncommon, and it puts the lie to the idea that you will always be racing against talented opponents in iRacing.
In the meanwhile, developers of titles like Project Cars, Assetto Corsa, and others were perfecting their AI racers to provide some level of decent competition, while they also worked on their online racing components. As of Project Cars 2 with update 1.3, the AI has risen to what I personally consider to be very close to racing in the rookie classes of iRacing, if not actually better. While the online racing against human opponents still has a way to go to truly compete with iRacing, I'm finding that I really don't care. Yeah, with iRacing I can race against a total stranger in Brazil, but since it's a total stranger, what do I care if it's a real person or simply good AI?
Hint: I don't. And with the convenience of being able to start (or restart) a race any time I want to, even if I did care the benefits of said convenience are easily enough to tip the scales in favor of something like PC2.
Will I renew with iRacing once the AI is in place? I really don't know. I have a ton of iRacing cars, none of which model the electronic in-car race displays as well as PC2 does. I have a ton of laser-scanned iRacing tracks, but so does PC2, with notable exceptions of tracks I like such as Lime Rock Park and Mid-Ohio and I'm not sure I would pay $10 a month for those.
It is obvious now that iRacing sees the emerging threat - have they responded soon enough?
Only time will tell.
The pertinent text from iRacing:
Ok, this will be a “shocker” to some. We are working on AI/Artificial cars and in fact very far down the road with the project. In fact, we should release it this year as well. Hardcore folks take a deep breath. We are not straying even the slightest from our philosophy of trying to create the most accurate and detailed simulation we can along with the best head to head racing competition. This has been an isolated project being done by a small team and has not impacted any other development.
However, having this feature will allow for many opportunities for members and for us to continue to grow. It will allow members to practice in a simulated setting before getting on track with real cars which is a good thing, especially for people new to sim racing. It will also allow for a more relaxed and fun format which will be a welcome addition from time to time for even hard-core members. Now you don’t need to go to another racing game for AI. Ha Ha. It will bring in many new members who will use it as a stepping stone to head to head racing. It allows us to have a much more competitive demo option for potential new customers in various settings like trade shows or even on-line trials. At the end of the day, it is a huge feature and request in regard to the overall market. It will be a free addition to members and yet another option for you under your membership. If AI [is] not for you, great, but you will still benefit. The work has helped improve our multiplayer net code and player car code which will be out on members about the time we launch AI.