Is it reasonable to think that most magic users would be familiar with the spell Silence and thus know easy ways to counter it?

Question

The spell Silence as described in the PHB:

For the Duration, no sound can be created within or pass through a 20-foot-radius Sphere centered on a point you choose within range. Any creature or object entirely inside the Sphere is immune to thunder damage, and creatures are Deafened while entirely inside it. Casting a Spell that includes a verbal component is impossible there.

The spell is obviously a useful tool against magic wielders, but I'm trying to get clarification on its limitations.

Would it be common for magic users to recognize the Silence spell and know easy ways to counter its effects? For example, a wizard familiar with the spell might know to just run a short distance in any direction to leave its area of effect, and then continue casting spells. I understand that different types of characters will have different knowledge of spells, but Silence isn't a high level spell and would seemingly be well known to many mid- and even low-level magic users.

The related question below might shed light on how a character would react to the Silence spell, because they might instead interpret the effect as being deafened.

Related questions:

Deafness vs Silence - How to distinguish Darkness from being blinded and Silence from being deafened?

Answer 1

Consider using an arcana check.

An optional rule in Xanathar's allows a character to make an Arcana check to understand the effects of a spell being cast. (see https://rpg.stackexchange.com/a/111123/21179) Anyone who passes this check should be assumed to understand the radius of the effect.

Think about worldbuilding.

I once played in a game world where magic users were rare and secretive, so nobody knew anything about anyone else's spells. (And to add to this, whenever we encountered an enemy spellcaster, the spellcaster would be using spells the DM had invented, so we would be as surprised by their spells as they would be by ours.) In a world like that, we should expect most spellcasters would not be familiar with even a low-level spell like silence.

In most of the D&D worlds, NPCs with adventurer character classes are uncommon. So, just because the cleric in the adventuring party can prepare silence, that doesn't mean that every religious person in the world is a cleric who can do that.

If the DM is feeling creative, the DM might actually have invented different powers for NPCs. So maybe there's one NPC spell that curses an individual person with a silence-like effect, a second NPC spell that generates a 20-foot sphere of silence, a third NPC spell that generates a mile-wide radius of silence, a fourth NPC spell that generates silence within that NPC's field of vision, and a fifth NPC spell that doesn't actually generate a silence effect but just deafens you so you think you're silenced. In a world like that, a spellcaster discovering they're silenced might be genuinely unsure which countermeasures are appropriate.

Many spellcasters are not well-educated. A sorceror has magic in their blood which lets them call forth fire and lightning, but they may not have studied magic formally and they may not know about any spells they can't personally cast. A cultist might have gained power through dark sacrifices to long-forgotten gods, but again that doesn't come with knowledge about wizard and cleric spells.

At the other end of the spectrum, in a setting like that of Adventurers League, it's assumed that adventurers with spellcasting classes are pretty common, and we should expect anyone who has seriously trained for combat (of any class, not just a spellcasting class) should have a good understanding of the capabilities of the standard character classes.