Some definitions of casual:

- relaxed and unconcerned
- made or done without much thought or premeditation
- done or acting in a desultory way (desultory means lacking a plan, purpose, or enthusiasm)
- done or acting without sufficient care or thoroughness

- not regular or permanent
- employed or established on a temporary or irregular basis
- (of a sexual relationship or encounter) occurring between people who are not regular or established sexual partners

- happening by chance; accidental

- without formality of style or manner, in particular (of clothing) suitable for everyday wear rather than formal occasions
In theory, all of FFXIV group PVE contents can fit many if not all those definitions (sex and clothing not applied directly, of course).

However, in practice, people's expectation (especially in the NA data center) can make them not casual, and a clear division can be seen between content that people will normally do without the use of party finder and contents that people will normally do with the use of party finder. I would consider the former to be casual content, in general, while the latter to be non-casual content, in general.

Extreme trial may be unique in that it can be difficult enough to warrant people using the party finder, but at the same time, farming mounts from it is also better with a fixed group, so a party finder is recommended either way. So maybe extreme trial content can be seen as a midway content between casual and non-casual.

Also, I use non-casual instead of hardcore because hardcore does not seem to fit well when used in comparison unless in a very specific application.

Some definitions of hardcore:

- Intensely loyal; die-hard
- Stubbornly resistant to improvement or change
- Extremely graphic or explicit
So, the only way the term "hardcore vs casual" (or vice versa) makes sense is if you define hardcore as being committed (loyal) while casual just means you're not committed (matches with doing things irregularly or temporarily). If you're raiding in a static, you're a hardcore member of the team. If you are pugging or you move around between statics, you're casual. If you're dedicated to raiding even if it means pugging, then you're a hardcore raider. If you try to raid, then take breaks often when pf fails you, then you're a casual raider.

So this applies to any content. If you're dedicated to doing roulettes every day, then you're hardcore at doing casual group PVE content.