Andy is correct: any two voltage regulators will always have slight manufacturing variation in their voltage set-points, which causes uneven distribution of the load current. So regulator outputs should not be directly connected together.
In the comments you mention the requirement to scale your 5 optocoupler design to power 15 optocouplers. So it may be possible to separate your total system's load current into smaller branches, and use multiple 100mA regulators.
Instead of connecting the second LM7L05 to the first one, why not use a
point of load regulator configuration. The first LM7L05 (U101) would supply 5V_BANK1 to power the first 10 optocouplers (U110-U119), and a second LM7L05 (U201) would supply 5V_BANK2 to power another 10 optocouplers (U210-U219). Both U101 and U102 have the same higher-voltage input, but each has its own separate 5V output.
simulate this circuit – Schematic created using CircuitLab
Since the regulator outputs are independent, the slight variance between 5V_BANK1 voltage and 5V_BANK2 voltage doesn't matter: as long as they are both within the 4.75V to 5.25V spec for each of the devices being powered. And it's also perfectly OK to drive logic signals from one bank to another bank, since they are all "5V logic" signals and they all have the same ground.
This point-of-load regulator architecture is commonly used in large systems. Power distribution is handled with relatively higher voltages, and a very small regulator serves each independent sub-circuit. This approach can help isolate noisy digital switching circuits from noise-sensitive analog circuits, and helps spread heat dissipation more evenly.