The meaning and the usage of the expression: "I dare say"

Question

Some dictionaries have defined the expression "I dare say / daresay" as spoken one and some other ones have defined it as a formal expression!

Meanwhile, some dictionaries consider it to be old-fashioned, and some other have not say anything about its fashion!

The same goes for the BE/AE difference. References have mentioned that it is chiefly BE and some of them have not brought up anything in this regard!

I wonder what can I say as a spoken idiom/expression which can be understood by both BE and AE native speakers which is in common use in current English (not dated)? I wonder if the same expression (I dare say) works itself (in current spoken AE/BE.)

Please note that to me it has the connotation of "I suppose" with a slight undertone of rebellion toward oneself (hence, it is spoken.)

• I saw her in a shop which sells pregnancy clothes yesterday. I dare say she is pregnant. (= I suppose.)
  

Answer 1

As an American, yes, I would consider the phrase to be associated with both BE and out of date. We might even use it when doing an impression in jest of an old British gentleman.

I think in this case it's being used to denote that what follows it is something which should not be said (because it's rude, scandalous, improper, impolite, etc.), but is being said anyway.

A modern way of restating it would be:

I saw her in a shop which sells pregnancy clothes yesterday. I know I shouldn't speculate, but I think she is pregnant.

Modern slang with similar uses would be "low key":

I saw her in a shop which sells pregnancy clothes yesterday. Low key, I think she is pregnant.