Largest recoverable physical scale vs line sensitivity (over 10 km s⁻¹) for archival ALMA observations, in Band 6 and 7, of the 16 nearby Class II YSOs associated with RNe, as discussed in Sect. 3. Marker colours denote the exposure time for each observation in minutes. The vertical dashed line denotes a recoverable scale of 1000 au. The horizontal dashed line denotes a line sensitivity of 2.3 mJy beam⁻¹ (the line sensitivity reported in the ALMA archive for SU Aur observations by Ginski et al. 2021). Markers with open circles denote the observations discussed in Sect. 3, with red circles for HD 142527, black circle for S CrA, and an orange circle for HD 97048.