Suppose an 8-year-old, a 30-year-old, and a 60-year-old walk into your club, all beginners, and sign up for lessons. Suppose you were their coach. You'd likely start them off similarly, teaching the fundamentals. But something happens after a time - how you teach them begins to change quite a bit. You, the reader, should decide where in this spectrum your game fits, and perhaps discuss it with your coach (if you have one) or take it into consideration when developing your game.
For the 8-year-old, you'd soon be teaching him "modern" table tennis - like, say, Ma Long. Once he has the fundamentals down pretty well, he'll likely be taught to stay pretty close to the table, loop from both sides, with feet mostly parallel to the table, even for forehands (except when forced off the table). He'll become a great counter-looper. He'll mostly serve seemingly simple short backspin/no-spin serves - third-ball attack serves - and follow them with loops. (He'll learn other variations, but they will be "surprise" serves, not his core serves that set up his third-ball attack.) He'll learn to attack short serves with backhand banana flips. And he'll be well on his way toward being an elite player, maybe a contender for the National Team or more!!!
Many coaches would teach the 30-year-old the same way, but that's probably a mistake. If he's a truly top-notch athlete, then perhaps you would teach him the same way. But in essentially every case, he's not ever going to be in contention to be a National Team Member. His goals are probably to be as good as he can be - perhaps someday a 2000-level player. For this player, you would likely teach him a bit different - more "old-school." He'll learn to loop the backhand against backspin, but in rallies, he might be better off hitting and blocking aggressively. He probably should move the right foot (for righties) back some for forehands, and not try to jam the table when looping. He'll learn to counter-loop, but he'll pick and choose when to do so rather than trying to do it almost every time. He should learn to flip serves but should probably focus more on pushing them back effectively. And while he should develop short backspin/no-spin serves, he'll develop a wider variety of serves, especially deep ones - serves that don't work as well at the higher levels but can be dominant against players under 2000 and often higher.
Of course, you should check with the 30-year-old to see what his goals are. He may want to play like Ma Long, in which case you'd coach him the same as that 8-year-old. (You should warn him that he'll need to put in a lot of hours to make up for lost time and have to be in pretty good shape physically.) How about a 20-year-old? He's in between, and depending on his goals and fitness level, you might teach him like that 8-year-old.
How about the 60-year-old? Unless he's a super-athlete for his age, he's not going to learn to run around all over the place looping. To reach his potential, it might be better to develop a great blocking game, and perhaps a good smash. He might learn to forehand loop against backspin, but in rallies he should probably mostly hit the forehand. He'll develop the trickiest deep serves he can, though he should also learn to serve short. He might learn to backhand loop against backspin, but often he'll be better learning to push, block, and hit. In fact, if his goal is to be as good as he can be, then (and some won't like this), very often he should go to long pips on the backhand, even early on. That's the dominant style at the older age groups, and there's a reason for it - the long pips is basically an "equalizer," allowing them to better block an opponent's athletic loops and turn all of that topspin into change-of-pace backspin. Another option is short pips, which can help with blocking and hitting.
Of course, you should also check with the 60-year-old to see what his goals are. He may want to play like Ma Long - but unless he's in great shape, I wouldn't recommend that as he'd probably hurt himself! But he might want to play with "regular" rubber, rather than face the stigma some long-pips players get, or he might want to play more of a topspin game.
In the end, players have to decide what their goals are. I've considered using long pips on my backhand a few times, but I just prefer sticking with inverted, so I win or lose using roughly the same equipment as the large majority of my opponents - plus, as a coach, I'm a better practice partner this way, both in drills and games. But everyone has to make the best choice for themselves!