I've played quite a bit of C&C Tiberian Dawn. Having sat on the leader boards in the top 200 for 2 weeks after launch and now sitting at 270 on average, here are my thoughts.
First, there's a very good reason that Tiberian Dawn's multiplayer is nearly dead while RA has lots of games being played. Balance. To the people talking about Mammoth tanks and obelisks, those don't exist in the leaderboard. Ranked players don't even build radar stations because that's money that goes to units. Nod can completely overhwhelm GDI with bikes and buggies within 4-5 minutes so there's no way you can afford to tech up and get enough units mobile enough to protect your harvesters. High rank GDI doesn't exist with the exception of players who cheese by learning all the map spawns and moving their MCV directly to your base at the start of a game to rush you with grenadiers. Aside from that GDI doesn't exist at high level play. With the exception of a few maps due to choke points (it should be clarified in the ranked pool almost none of these maps are present), the majority of maps allow Nod to completely overwhelm opponents with cheap units from multiple entry points at once. GDI has no real response to attack bikes unkless the playing microing them is sloppy, lagging, or the GDI player has literally every entry point to their base covered which only works until their harvesters need to leave the safety of their base which doesn't take very long. Even in the scenario where GDI holds off Nod at their base, for every 3 tanks GDI can afford, Nod has 2 and a half bikes that are much more manouverable. GDI leaves their base with their slow wall of tanks and turns the game into a base race Nod wins due to faster units + numerical advantage. Tht's before you even consider time factors, not just money factors.
Nod is basically all there is at top play unless GDI players spam rush grenadiers. Your other option is engineer cheese which basically doesn't exist in RA which is why Tiberian Dawn is inferior in multiplayer. Red Alert has decent balance, Tiberian Dawn has one effective faction.
If you're building high tech units in ranked you've already lost, sorry, or at an extremely low level of play. And static base defenses wont stop 20-30 bikes from poaching your harvesters with complete impunity, andonce your economy is crippled and Nod has total map control because they can outrun all your units, you're either forced to base race vs faster, larger groups of units or wait until the number of bikes/buggies is so overwhelming you have zero chance of winning anyway. This is also ignoring a competent player can also just micro units to dodge tank fire which totally negates GDI's one actual advantage over nod in terms of vehicles which is raw fire power.
When I go into ranked and face GDI it's a 100% win unless they MCV rush and use grenadiers. Nod is king in this game. C&C is a great experience for SP but don't come in expecting to say you're good when most of the time you win is largely off the horrendous balance that renders GDI completely useless against even a semi-competent nod player.