Quote from SagaTympana >>

It's pretty clear that those of us who spend our time here would really appreciate tighter, more formalized rules language. Let's hope the core rules revamp in 2024 addresses some of this.

Agreed. This thread wouldn't exist if the rules for counterspell said, "* - which you take when you see a creature within range casting a spell" :-)

I'm in the "distant metamagic affects range not aoe" camp, so i'd rule that it has no effect on sunbeam.

Here's one thing that might help from 252 of the DMG

Adjudicating Reaction Timing

Typical combatants rely on the opportunity attack and the Ready action for most of their reactions in a fight. Various spells and features give a creature more reaction options, and sometimes the timing of a reaction can be difficult to adjudicate. Use this rule of thumb: follow whatever timing is specified in the reaction's description. For example, the opportunity attack and the Shield spell are clear about the fact that they can interrupt their triggers. If a reaction has no timing specified, or the timing is unclear, the reaction occurs after its trigger finishes, as in the Ready action.

I read that as saying the timing of reaction spells are subsequent to their trigger rather than simultaneous. And also lays out a distinction between AoO and shield and other reactions.

Quote from SagaTympana >>

I'm gonna pick out this bit to address, because it's the part I think is important. All I have to say to it is: why?

 You're right. I'm caught up in analyzing a process as I understand it. If we remove any distinction between casting range and trigger range, it may not matter at all.

Quote from _Amunsol_ >>

Here's one thing that might help from 252 of the DMG

Adjudicating Reaction Timing

Typical combatants rely on the opportunity attack and the Ready action for most of their reactions in a fight. Various spells and features give a creature more reaction options, and sometimes the timing of a reaction can be difficult to adjudicate. Use this rule of thumb: follow whatever timing is specified in the reaction's description. For example, the opportunity attack and the Shield spell are clear about the fact that they can interrupt their triggers. If a reaction has no timing specified, or the timing is unclear, the reaction occurs after its trigger finishes, as in the Ready action.

I read that as saying the timing of reaction spells are subsequent to their trigger rather than simultaneous. And also lays out a distinction between AoO and shield and other reactions.

 And Xanathar's Guide to Everything also reiterate it:

If you’re unsure when a reaction occurs in relation to its trigger, here’s the rule: the reaction happens after its trigger completes, unless the description of the reaction explicitly says otherwise.

Thanks everyone for your contributions. I think I better understand the RAW of this particular technicality, which is much of what I was after. I think I'm still in favor of allowing increased range on reaction spells, saying that rules aside, these actions all happen in quick enough succession that its justifiable to say when you see someone casting a spell past 60 feet you can add your meta magic to increase the trigger range. It feels too willy, nillly to me to make that the case without understanding the rules first.

Quote from SagaTympana >>

Quote from Plaguescarred >>

A Distant Counterspell would look like this;

Counterspell

3rd level abjuration

Casting Time: 1 reaction, which you take when you see a creature within 60 feet of you casting a spell

Range: 120 feet

For those interested it's already been answered by the Dev; https://www.sageadvice.eu/can-distant-spell-be-used-to-increase-the-reaction-trigger-requirement-for-counterspell-to-120-feet/

@James62888542 Can Distant Spell be used to increase the reaction trigger requirement for Counterspell to 120 feet? It seems like the reaction trigger of 60 feet must be met before you can cast Counterspell, which is before you could apply Distant Spell. Thanks! 

@DaveWil33 Yeah, mechanically the distance in the trigger is not the range of the spell so even if you did have some kind of passive spell range increase it wouldn't affect that. 

@JeremyECrawford Dave is correct.

 He's answering the question as if the 5e books are written the way the 4e books were, which they're not. I'm just as guilty as examining the rules legalistically as everyone else who frequents this forum, but I'm trying to do better and to read 5e as it is, not as I wish it were. And as it is, the triggering range is obviously the range of the spell, because that's how any casual reader would take it. The rules are quite literally explicitly designed to resist the level of scrutiny we're applying.

It's pretty clear that those of us who spend our time here would really appreciate tighter, more formalized rules language. Let's hope the core rules revamp in 2024 addresses some of this.

 You nailed it here. I feel like I want to quote this post in my signature or something. It's a little long for that, lol

I really wouldn't mind if they made it more formal... Or less. But this middle ground it's in now, I don't love.

I have been saying this about 5e for ages, but this subforum exists to put the written rules under a microscope. It is what it is.