Since It seems you are new to the game I will explain.
1) You soft lock yourself out of MGs, Mortars and most important ATGs.
2) Penals bleed very easy due to their RA and they cost a lot to reinforce specially early on.
3) They have 0 utility. They are either decent AI or Shitty AT atm.
4) Building T1 for sniper means that you basically pay 500 mp and 10 fuel just to get a single unit and if you get something else from T1 then you lose all early map presence and will struggle to get any ground.
5) No snares meaning that since you don't have any AT measures you will struggle to fight vehicles.
Clown car + Penals against OKW is the only semi-viable thing in T1 atm. Or if you are for example VonIvan\Kimbo you might pull off T1 against anyone.
All of this for 1v1 and most of this for team modes.
Add to this that T1 + Penals or Sniper is a huge waste of resources and at the same time a terrible presence on the map, the enemy dominates from the start: in the number of units, in the capture of points and resources. Somewhere in 3 vs 3 it can be neutralized because of allies, but 1 vs 1 or 2 vs 2 is in most cases you will guarantee yourself a loss.