It seems that the committee is being deliberately hostile to Java applets.
This is based on the fact that, with the proposed change, it will no longer be
possible to include an applet in such a way as to be compatible with all
browsers that support applets. It is desirable to write HTML code that will
work on all browsers that support the required features. There are older
browsers that recognize Java applets but predated any alternative to the
<applet> tag. Conforming to the proposed new standard requires breaking such
browsers. And the incompatibility is completely unnecessary. There is no
justification for breaking older browsers on that point. The <object> syntax
is messier (because it tries to handle more things than just applets.) The
original setup for applets had a simple, readable design. The new proposal is
convoluted and unreadable and will not work on some browsers. Standards should
increase compatibility, not restrict it.