Remasters - are they better? What exactly is it?

You can pretty much tell what decade something was recording by the quality of the recording.

Nonsense. Like many things in life, recording quality is a bell curve.

a flat transfer of the original analogue master tapes is best, nothing added and nothing taken away

a flat transfer does not exist. Tape machines have EQ curves aligned at 3 points: 100Hz, 1KHz and 10KHz. If the original was recorded on an ATR-102 and the copy is made on a pair of Otari / Studer / MCI, the sound will change - sometimes drastically.

When I was a recording engineer, if I wanted a ’faithful copy’, I schlepped my 2T to the studio and made a ’master’ off the 2T buss.

There can be differences between CDs that are not remasters, but just later pressings. Someone decides the recording needs a little ’help’ and messes about. See an example from Fagan’s Nightfly track I.G.Y. see http://ielogical.com/Audio/#ReIssues

The recent remastering of The Beatles album Abbey Road is a good example of a clear improvement in sound

Crime of the Century is killer on vinyl.

That probably depends on what ’original’ you had. see http://ielogical.com/Audio/#Origins

If you were weaned on 80’s or later pop recordings, please don’t post. ~<:-P

I’m just not sure how someone can disagree that there’s not a huge difference in the sound of older stuff vs newer stuff.. Maybe you like that old nostalgic sound.. If you do, I’d say save your money on great audio equipment though because it matters much less.

There’s a huge difference in sound quality between recordings in any era. If by newer stuff you mean the moronic millennial whoop that passes for music today, then please do us a favor and don’t post about sound quality. THERE IS NONE!!!

As far as equipment, the better it is, the better good recordings sound.
Systems must be neutral. If they impose their coloration, only a small subset of recordings will sound acceptable thereupon.

I have CDs of recordings going back to the 30’s. Some of them are every bit as engaging as anything recorded today. Frank Sinatra’s "Songs for Swinging Lovers" recorded January 1956 in mono emotes every bit as much as Nora Jones or Diana Krall or ??? The Andrews Sisters collection kicks the proverbial butt. Joe Pass sits front and center in the media room. Queen Will Rock You.

someone who claims to be a sound engineer

https://www.discogs.com/artist/273206-Ian-Eales
I quit because I couldn’t stand the grooveless computer crap. In that era, computers were 1½ orders of magnitude worse time wise than good musicians. There just wasn’t enough shellac...

Over the last twenty years or so a lot of pop/rock music has increasingly been mastered for play on car stereos, mobile devices, and earbuds.

A lot of content today is reduced bitrate. OTA radio stations 'rip' material to MP3 for smaller storage. For a visual on how bit-rate reduction distorts the music, see http://ielogical.com/Lossy/ 

Those of us who insist on listening to music on a quality system are probably now in the minority.

No probability about it. We always have been and likely always will.

Sadly, the great unwashed think they have a quality system, but it can be egregious. More than once, I've asked that a system be stopped or I shall have to leave. I literally become nauseous from the swirling dervishes caused by bitrate reduction. I stream reduced bitrate, but playback is mono.

 The first series of Classic Records RCA reissues cut directly from the master tape with very little EQ or change.  Listeners were unhappy because they did not hear "better" versions of what they were intimately familiar with !  What they received was actually closer to the master tape, but we deemed inferior !   Classic incorporated some of the original EQ in subsequent reissues.

What idTENt decided to leave off mastering EQ?

Back in the day when the distribution media was vinyl, mix engineers backed up from the disc knowing it would add a bit of coloration.

It was sometimes a hassle with new acts because they did not understand that what they heard in the control room or a from a cassette in their car was not the 'finished' product. We called it "Fixing it in the stores"