Airlines have always taken minimal hours pilots (whether from their own integrated training schemes, or modular hours builders), if that's no longer the case I'm wondering how they are to fill the positions in future
Not in the 42 years I have been flying for them. Usually the only sourced low hour pilots have come from their own cadet schemes ( where they have them). The other two primary sources have been career advancers and ex-military. In recent years the latter group has decreased as a primary source and probably to the extent that the cadet group has increased. For the career advancers it is usually those with the better experience. A lot of pilots would traditionally instruct, fly out in Africa or Asia or look for “aerial work” opportunities that would provide the hours and exposure that would eventually lead to an airline interview. The airline “jet jobs” would be the pinnacle level of many of those aspirants.
To whatever extent, and in whatever proportion that is likely to be the case well into the future. I cannot see any shortage of significant experience within the next 5 years just from the redundant pilot group and the build up of the traditional sources. As cadet schemes come back on line it is likely to be from the same selective programmes.