Edit: M Oehm found this before me!

Partial Answer

See M Oehm's answer.

Note that:

Quite a few of the numbers inside the parentheses are divisible by 3.

Other observations

1. The middle paragraph consists of four lines that have the following number of words each: 11, 8, 11, 8. This seems to be intentional, because the word "spend" would definitely fit in the previous line.
2. The following phrases contain exactly 16 letters: "It has been too long", "Since we tested you" and "The first number is". Maybe this is just a coincidence.
3. The last sentence has no period. This is odd, because everything else is "correctly" written.
4. There are at least 3 different characters for '0': Maybe some of them are 'O' or 'o' (the letters), or maybe it's a "smart" font that changes the characters to make them look more natural.

Edit: M Oehm found this before me!

Partial Answer

See M Oehm's answer.

Note that:

Quite a few of the numbers inside the parentheses are divisible by 3.

Other observations

Edited after comments from the OP.

1. The middle paragraph consists of four lines that have the following number of words each: 11, 8, 11, 8. This seems to be intentional, because the word "spend" would definitely fit in the previous line.
2. The following phrases contain exactly 16 letters: "It has been too long", "Since we tested you" and "The first number is". Maybe this is just a coincidence.
3. The last sentence has no period. This is odd, because everything else is "correctly" written.
4. There are at least 3 different characters two characters for '0' (One wide and one narrow, "The two narrow ones[...] are intended to [be] the the same character"):

Edit: M Oehm posted this 9 minutes before me!

Partial Answer

If the contrast is increased, a faint code appears:

Transcription:

016:-6(28,12,30,30)-4(12,5,15)-7(12,15,10,11,6,15,12,21)

Note that:

Quite a few of the numbers inside the parentheses are divisible by 3.

Other observations

1. The middle paragraph consists of four lines that have the following number of words each: 11, 8, 11, 8. This seems to be intentional, because the word "spend" would definitely fit in the previous line.
2. The following phrases contain exactly 16 letters: "It has been too long", "Since we tested you" and "The first number is". Maybe this is just a coincidence.
3. The last sentence has no period. This is odd, because everything else is "correctly" written.
4. There are at least 3 different characters for '0': Maybe some of them are 'O' or 'o' (the letters), or maybe it's a "smart" font that changes the characters to make them look more natural.

Edit: M Oehm found this before me!

Partial Answer

See M Oehm's answer.

Note that:

Quite a few of the numbers inside the parentheses are divisible by 3.

Other observations

1. The middle paragraph consists of four lines that have the following number of words each: 11, 8, 11, 8. This seems to be intentional, because the word "spend" would definitely fit in the previous line.
2. The following phrases contain exactly 16 letters: "It has been too long", "Since we tested you" and "The first number is". Maybe this is just a coincidence.
3. The last sentence has no period. This is odd, because everything else is "correctly" written.
4. There are at least 3 different characters for '0': Maybe some of them are 'O' or 'o' (the letters), or maybe it's a "smart" font that changes the characters to make them look more natural.